: -3=3 m FUNGOID PESTS OF CULTIVATED PLANTS y n ( BY M: C. COOKE, M.A., LL.D., V.M.H., A.L.S. Reprinted from the Journal of tbe IRosal Iborttcultural Society Vols. XXVII.— XXIX. LlBMIAtV *gW YO*K OA*»tiN ptinteb bi) SPOTTISWOODE & CO. LTD., NEW-STREET SQUARE, LONDON 190G [All right i a LMARV CONTEXTS. INTRODUCTION .... PESTS OF FLOWER GARDEN . Ranuncclaceous Plants Violet ahd Pansy. Caryophyllace.e Roses Composite Plants Primroses ScROPHULARIACE.E Endogenous Flowering Plants Fern Diseases PESTS OF GARDEN VEGETABLES . Mushroom Parasites PESTS OF ORCHARD AND FRUIT GARDEN PESTS OF VINERY AND STOVE Conservatory Parasites PESTS OF ORNAMENTAL SHRUBBERY Coriaceous-leaved Shrubs Deciduous-leaved Shrubs Gymnosperms PESTS OF FOREST TREES PESTS OF FIELD CROPS . Cereals and Grasses Dicotyledonous Plants FUNGICIDES INDEX I'AGK 1 9 9 23 29 42 50 53 62 62 78 79 107 109 152 162 176 177 186 196 l'.i:t 229 229 243 252 ■J .-.7 ILLUSTBATIONS. I. PESTS- rL, ATE S. -FLOWER GARDEN . II. 11 » JJ • • III. 11 11 JJ • ■ IV. »1 )' 11 V. J1 11 51 • • VI. 11 )1 l» • • VII. 1» GAEDEN VEGETABLES . VIII. 11 11 11 IX. 11 JI JJ X. 11 OECHAED, etc. . XL H 11 ... XII. 11 11 ... XIII. 11 VINERY .... XIV. 11 &c XV. Jl CONSERVATORY XVI. 1» ORNAMENTAL SHRUBBERY XVII. 1) 11 j» XVIII. J? 11 11 XIX. n FOREST TREES XX. n M 11 * XXI. 11 » 11 ■ XXII. i> FIELD CROPS . XXIII. »i ii i: XXIV. u n ii to face page 8 u 24 >i 38 JJ 52 J) 62 11 (14 JJ 68 )) 94 n 102 n 118 11 124 ii 132 ii 152 11 156 »» 166 jj 176 ii 182 ii 190 ii 198 i» 208 ii 220 n 230 ii 236 246 IN TEXT. I'AGK Fig. 1. — .Ecidiospore germinating 5 2. — Teleutospore germinating 6 3. — SCLEBOTINIA TUBEROSA, NATURAL SIZE ; ASCUS AND SPOBIDIA x 400 . 15 4. — Ovdlaria Clematidis 20 5 — (1) Rose Leaf, blotched with the Mildew. (2) Chains of Conidia. (3) conilicm germinating . 45 6. — Endophyllum Scmpervivi attacking Seiwpervivum monticolum . . 47 7. — Endophyllum Scmpervivi . 48 ILLUSTRATIONS. Fig. 8.- Botrytis Species 9. — Ubomtces Erythronii 10. — botrytis galanthina, a parasite on snowdrops 11. — Xylaria VAPORARIA 12.— Apple Mildew (Sphcerotheca Mali) 13.— Ectypella Prunastri 14. — EuTYrELLA Prttnastri, causing a Disease of Nurseks Stock 15.— Spji/eroi'sis Malorum 16. — Pear-leaf Cluster-cup •. . 17. — Twig ok Cherry infested with Gnomonia erythrostoma 18.— Brown Rot of Fruit (Moniliu fructigena) 19. — Tree-root Bot (ArmUlaria mellea) . 20. — Fomes fohentarius .... 21. — Sphcerotheca Humdli 22.— Anthracnose of the Vine. 23. — Protomyces concomitans PAGE 65 68 72 109 112 114 116 118 121 129 136 141 143 151 154 171 Vll EXPLANATION OF PLATES. (The magnified portions are x 320 diameters, unless where otherwise stated.) PLATES I.— IX. Pests — Flower Garden and Garden Vegetables. Fig. 1. — Phyllosticta helleborella , Sacc— a, section of perithecium enlarged; b, sporules x 2. — Septoria Hellebori, Thum.— a, section of perithecium enlarged ; b, sporules x 3. — Coniothyrium Hellebori, C. & M.— a, sporules x 4. — Ramidaria Hellebori, Fckl. — a, threads and conidia x 5. — Peronospora Ficarne, Tul. Hyphas and conidia x 6. — Plasmopara pygmcea, Ung. Hyphre and conidia x 7. — Urocystis Anemones, Pers. — a, glomerules of spores x 8. — JEcidium punctatym,'Pers. Two cluster- cups enlarged. — a, recidiospores x 9. — Glceosporium Aquilegice, Thum. — a, conidia x 10. — Ascochyta Aquilegice, Kourn. — a, section of perithecium enlarged ; b, sporules x 11. — Phyllosticta Pcvonue, S. & S.— a, section of perithecium enlarged; b, sporules x 12. — Cronartium Pceonicv, Cast.- a, column enlarged ; b, sporules x ; c, sporules germinating x 13. — Cladosporium Pceonice, Pass. Hyphse and conidia x 14. — Botrytis Pcsonice, Oud. Clusters of conidia in situ x 15. — Peronospora arborescens, Berk. Portion of thread with conidia x 16. — Cercospora Reseda, Fckl. — a, hyphse and conidia x 17. — Phyllosticta Viola, Desm.— a, section of perithecium enlarged ; b, sporules x \S. — Septoria Violce, West.— a, section of perithecium enlarged ; b, sporules x 19. _ Urocystis Violce, Fisch. — a, glomerule of spores x 20. — Puccinia Violce, Solium, -a, uredospores ; b, teleutospores x 21. — JEcidium Violce, Schum. — a, cluster-cups ; b, aecidiospores x 22. — Puccinia cegra, Grove.— a, secidiospores ; b, uredospores; c, teleutospores x 23. — Eamularia lactea, Desm.— a, threads and conidia x 24. — Peronospora Violce, DBy. Hypha with conidia x 25.— Alternaria Violce, Gall. — a, conidia ; 6, germinating x 26. — Cercospora Violce, S. — a, hyphse and conidia x 27 .—Phyllosticta Dianthi, West.— a, section of perithecium enlarged ; b, sporules x 28. — Ascochyta Dianthi, A. & S. With sporules x 29— Septoria Lychnidis, Desm. With sporules x SO.— Peronospora parasitica, Pers. Hypha with conidia x 31.— Septoria Sinarum, Speg.— a, section of perithecium enlarged ; b, sporules x 32,—Marsonia Delastrei, De Lacr. — b, conidia x 33. — Ustilago violacea, Pers. — a, anther ; b, spores x Si.—Sorosporium Saponariai, Hud.— a, glomerule of spores x 35.— Puccinia Dianthi,DG.—a, uredospores; b, teleutospores x 36.— Puccinia Silenes, Schr.— a, uredospores; 6, teleutospores x 3T.— Uromyces Dianthi, Nssl.— a, uredospores; b, teleutospores x 38. — Macrosporium nobile, Vize.— a, conidium x ■69.—Heterosporium echinulatum, lierk.— a, threads with conidia x 40.— Bacterium Dian thi, Ar. 400. 33. — Heterosporium minutulum, C. * M. — Hyphre with conidia x 400. PLATES XVI., XVII., XVIII. Pests — Ornamental Shrubbery. Fig. 1. — Exobasidium Rhododendri, Cram. — a, cluster of galls; b, basidium with spores x 350. 2. — Phyllosticta Arbuti, Desm. — a, section of perithecia ; b, conidia x 400. 3. — Septoria Unedonis, Rob. — a, section of perithecium ; b, conidia x 400. 4. — Phyllosticta Cookei, Sacc. — a, section of perithecium ; b, conidia x 400. a.— Capnodium Footii, Harv.— Perithecia with mycelium and sporules x 400. 6. — Phyllosticta tinea, Sacc. — a, section of perithecia ; b, conidia x 400. 7. — Phyllosticta Ligustri, Sacc. — a, section of perithecia ; b, conidia x 400. 8. — Phyllosticta limbalis, Pers. — a, section of perithecium ; b, conidia x 400. 9. — Puccinia Buxi, DC. — a, teleutospore x 400. 10. — Phi/llosticta hedcricola, D. d r M. — a, section of perithecium ; b, conidia x 400. 11. — Septoria insular is, B. & Br.— a, section of perithecium ; b, conidia x 400. 12. — Septoria Hederce, Desm. — a, section of perithecia ; b, conidia x 400. 13. — Glceosporium paradoxum, De Not. — a, section of pustule ; b, conidia x 400. 14. — Phyllosticta nuptialis, Thiim. — a, section of perithecium; b, conidia x 400. 15. — Phyllosticta Phillyrece, Sacc. — a, section of perithecium ; b, conidia x 400. 16. — Uredo Phillyrece, Cooke. — a, pustule enlarged ; b, uredospore x 400. 17. — Phyllosticta sanguinea, Desm. — a, section of perithecium ; b, conidia x 400. 18. — Phyllosticta ruscicola, D. & M. — a, section of perithecium; b, conidia x 400. 19. — Phyllosticta Mahonice, S. & S. — a, section of perithecium ; b, conidia x 400. 20. — Ovularia Berberidis, Cooke. — a, hyphse with conidia x 400. 21. — Glceosporium Berberidis, Cooke. — a, section of pustule ; b, conidia x 400. 22. — Microsphcera Berberidis, DC. — a, tip of appendage; b, ascus and sporidia x 400. 23. — JEcidium Berberidis, Gmel. — a, cluster-cups, enlarged ; b, aecidiospores x 400. 24.— JEcidium crassum, Pers. — a, section of cluster-cups, enlarged ; b, aecidio- spores x 400. 25. — Microsphcera divaricata, Wallr. — a, tip of appendage, enlarged ; b, ascus and sporidia x 400. 26. — Microsphcera Hedwigii, Lev. — a, tip of appendage, enlarged ; b, ascus and sporidia x 400. 27. — Cceoma Euonymi, Gmel.— a, uredospores x 400. 28. — Microsphcera Euonymi, DC. — a, tip of appendage, enlarged ; b, ascus and sporidia x 400. 29. — Phyllosticta cornicola, DC. — a, conidia x 400. 30. — Septoria cornicola, Desm. — a, section of perithecium ; 6, conidia x 400. 31. — Erysiphe tortilis, Wallr.— Receptacle with appendages ; a, ascus and sporidia x 400. 32. — Ovularia Syrmgce, Berk. — Tuftofhyphae bearing conidia x 400. 33. — Microsphcera Lycii, Lasch. — a, tip of appendage ; b, ascus and sporidia x 400. 34. — Fusidium Deutzice, Cooke. — a, tuft of conidia ; b, conidia x 400. Xll EXPLANATION OF PLATES. Fig. 35. — Glceosporium Mezerei, C. & M. — a, conidia x 400. 36. — Phleospora OxyncanthcB, Kze. — a, conidia x 400. Bl.—Podosphcera OxyacanthtB, DC— a, tip of appendage enlarged, 38. — Raestelia lacerata, Mcr. a. section of cups, enlarged; b, rccidiospore ■ 400. 39,—Phyllosticta Cytisi, Desm. — a, section of peritheciam ; o, conidia x 400. 40. — Rastelia cornuta, Gmel. — a, three cups, enlarged; b, secidiospores x 400. 41. — Gymnosporangium Sabhue, Dicks.— Pustule, nat. size; a, teleutospores x 400. 42. — Gymnosporangium confusum, Plowr. — Teleutospores germinating x 400. 43. — Coryneum Berkeleyi, Cooke. — a, section of receptacle ; b, conidia x 400. 44. — Gymnosporangium clavariiformc. Jacq. —Pustule, nat. size ; a, teleutospores x 400. 45. — Gymnosporangium juniperinum, L.— Pustules, nat. size; a, teleutospores x 400. 46.—SphareUa Taxi, Cooke.— a, perithecium enlarged; b, ascus and sporidia x 400. PLATES XIX., XX., XXI. Pests — Forest Trees. Fig. 1. — Phyllosticta Aceris, Sacc— a, section of perithecium enlarged ; b, conidia x 400. 2. — Phleospora Aceris, Lib. — a, section of perithecium ; b, conidia x 400. 'd.—Septoglccum Hartigianum, Sacc— a. twig with pustules; b, section of pustule ; c, conidia x 400. 4. — Botrytis depradans, Cooke. — Portion of capitulum x 400. 5. — Bhytisma acerinum. Fries. — a, conidia; b, ascus and ascospores x 400. 0. — Uncinula Aceris, DC. — a, receptacle enlarged; b, tip of appendage en- larged ; c, ascus and ascospores x 400. 7. — Bhytisma punctatum, Fries. — a, conidia; b, ascus and ascospores x 400. 9. — Glaosporium nervisequum, Fckl. — a, conidia x 400. 10 — Scptoria Hippocastani, 13. & Br. — a, section of perithecium ; b, sporules x 400. 11. — Stereum purpureum, Fries. — a, basidium with spores x 400. 12. — Phleospora Clmi, Fries. — a, section of perithecium; b, sporules x 400. 13 — Piggotia asiroidea, Berk. — a, conidia x 400. 14. — Phyllachora Ulmi, Fckl. — a, section of stroma ; b, ascus and ascospores x 400. 15. — Seploria Fraxini, Desm. — a, section of perithecium ; b, sporules x 400. 16. — Glozosporium umbrincllum, B. & Br. — Hyplne with conidia x 400. 17. — Microstoma album, Desm. — Basidia and conidia x 400. 1*. - Uredo Quercus, Brond. — a, uredospores x 400. 19. — Stereum hirsutum, Fries. — a. basidium with spores x 400. •in. sti ■rcum frustulosum, Fries. — a, basidia with spores x 400. 21. — Diaporthe taleola, Sacc. — a, pustules enlarged; b, section of stroma; c, conidia ; d, ascus and ascospores x 400. 22.— Phytophthora omnimra, Dl'y. 23. — Glceosporium Carpvni, Desm. — a, pustule enlarged ; b, conidia x 400. •J J.- Gnomoniella flmbriata, A. & B.- ". section ol perithecia enlarged; b, asco- spores x 400. 25. Phyllosticta betulina, Sacc. — a, conidia x 400. 2i;. Melampaora betulina, Pers. — a, uredospores; b, teleutospores ; c, teleuto- spm. - germinating x 400. 27. — Dothidella betulina,FrieB. — a, section of stroma enlarged; b, ascospores x 100. is. Septoria TiUcB,Weit. — a, section of peritheciam enlarged ; &,"oonidia x 400. 29. Septori >la, Cooke. — a, section of perithecium ; b, conidia x 400. 30. P ' bacilligera, Pres. — a, hyplnu with conidium ; />. conidia x 400. 81. Septoria Populi, Desm. — a, section of perithecium; b, conidia x 400. '■'>i. Marsonia Populi, Lib. — a, section of pustule ; b, conidia x 400. 83. QlcB08porium Tremula, Lib. — a, section of pustule ; b, conidia x 400. 84. \Lelamp ora Tremula, Tul. — a, uredospores; b, teleutospores x 400. 85. Mi amp ora cecidioides, DC. — a, uredospores; b, teleutospores x 400. 86.- Melampaora popuUna, Jacq. — a, uredospores ; 6, teleutospores x 400. 37.— Taphrvna aurea, Fries. — a, section of blister; b, ascus and spores; c, asco- jpore x 400. EXPLANATION OF PLATES. xiii Fig. 38. — Septoria salicicola, Fvies.— a, section of perithecium enlarged ; b, conidia x 400. 39.— Melampsora vitellina, DC. — Uredospoves x 400. 40. — Me lampsora mixta, Thiim. — Uredospores x 400. 41. — Melampsora epitea, Kunze. — a, uredospores ; b, teleutospores x 400. 42. — Melampsora farinosa, Pers. — a, uredospores ; b, teleutospores x 400. 43. — Bhytisma salicinum, Pers. — a, section of stroma ; b, ascus and ascospores ; c, ascospores x 400. 44 Uncinula adunca, Wallr. — a, perithecium with appendages, enlarged; b, ascus with ascospores x 400. 45. —Pcstalozzia Hartigii, Tub. — Conidia in various stages x 400. 46. — Peridermium Pini, Wallr. — a, cluster-cup, enlarged ; b, itcidiospores x 400. 47. — Peridermium elatinum, k. & S.--.Ecidiospores x 400. 48. — JEcidium pseudo-eolumnure, Kuhn. — a, cluster-cup, enlarged ; b, secidiospore x 400. 50. — Cceoma pinitorquum, Br. — a, secidiospores x 400. 51. — Nectria cucurbitida, Fries. — a, cluster of perithecia, enlarged ; b, ascospores x 400. 52. — Lophodermiuvi Pinastri, Chev. — a, perithecium enlarged ; b, ascospore x 400. 53. — Caoma Laricis, West. — a, ascidiospores x 400. 54. — Dasyscypha calycina, Fekl. — b, cup ; c, section ; d, ascospores x 400. PLATES XXII., XXIIL, XXIV. Pests — Field Crops. Fig. 1. — Ustilago Tritiei, Jens. — a, spores ; b, spores germinating with conidia x 2. — Tilletia Tritiei, Wint. — a, spores ; b, spores germinating with secondary spores and conidia x 3. — Puccinia Gram/mis, Pers. — a, uredospores; b, teleutospores x 4. — Puccinia Bubigo-vcra, DC. — a, uredospores ; b, teleutospores ; c, teleuto- spore germinating with conidia x 5. — Puccinia corona ta, Cord. — a, teleutospores x 6. — Fusarium eulmorum, W.G.S. — Mycelium with conidia x 7. — Septoria Tritiei, Desm. — a, section of perithecium enlarged; b, conidia x 8. — Septoria Graminum, Desm a, section of perithecium enlarged ; b, conidia x 9. — Ustilago Hordei, Kell. — a, spore; b, spores germinating x 10. — Ustilago nitda, Jens. — a, spores; b, spores germinating x 11. — Fusarium Hordei, W.G.S. — a, grain with its parasite ; b, Lyphae with conidia x 12. — Ustilago Avence, Jens. — a, spores ; b, spores germinating x 13. — Urocystis occulta, Wallr.— a, cluster of spores. 14. — Claviceps purpurea, Tul. —a, ergot of rye in situ ; b, ergot x 2 ; c, ergot with claviceps x 3 ; d, ascus with sporidia x 15. — Ustilago Maydis, DC. — a, swollen receptacles; b, spores ; c, spore germi- nating with conidia x «00 16. — Ustilago Beiliana, Kuhn. — a, spores ; b, spore germinating x 1000 17. — Fusarium heterosporum, Xees. — a, conidia x 18. — Erysiphe Graminis, DC. — a, receptacle x 40 ; b, ascus and sporidia x 19. — Oidium monilioides, Link. — a, chain of conidia ; b, conidia x 20. — Pltyllachora Graminis, Pers. — a, pustule enlarged; b, ascus and sporidia x 21. — Claviceps Wilsoni, Cooke. — a, clubs, nat. size ; b, club x 5 ; c, perithecia x 20 ; d, sporidium x 22. — Ustilago hypodytis, DC. — a, spores x 23.— Tilletia striAformis, West. — a, spores. 24.— Isaria fuciformis, Perk. — a, stroma enlarged; b, conidia x 25. — Fusarium insidiosum, Berk. — a, tufts enlarged ; b, conidia x 26. — Scolecotrichwm sticticum, B. & Br. — a, hyphos ; b, conidia. 27. — EpichloV typhma, Pers. — a, section of stroma enlarged; b, sporidium x 28. — Ustilago grandis, Fries. — a, spores. 29. — Puccinia Phragmitis, Schum. — a, uredospores; b, teleutospores x 30. — Uromyccs I'oce, Eabh. — a, uredospores ; b, teleutospores x 31. — Phyllosticta Cannabis, Kirch.— a, section of perithecium ; b, conidia x 32. — Melampsora Pini, DC. — a, uredospores; b, teleutospores ; c, teleutospore • germinating x 33. — Fusarium Lini, Poll. — a, conidia x 34. — Uromyccs Betce, Kuhn. — a, uredospores; b, teleutospores x xiv EXPLANATION OF PLATES. Fig. 35.— (Edomyces leproides, Trab.— a, spores x 36. — Phoma tabinca, P. & D.— a. perithecium bursting the cuticle ; b, section of perithecium enlarged ; c, conidia ; d, perithecium of ascospores ; c, ascus with sporidia ; /. sporidia free x 37. — Pseudopcziza Trifolii, Sib. — a, parasite in situ; b, cup breaking cuticle; c, section of cup enlarged ; d, ascus and sporidia; e, free sporidia x 38. — Sclerotonia THfoliorwm, Erik. — a, cups or stroma; 6, ascus and sporidia x 39. — Polythrincium Trifolii, Kunze. — a, section of tufts; b, conidia x 40. — Phyllachora Trifolii, Pers. — a, section of stroma x 41. — Peronospora Trifoliorinn. DBy. — Hyplne with conidia x 42. — TJromyces Trifolii, Hedw. — a, uredospores ; b, sori enlarged; c, teleuto- spores x 43. — Pcronosjwa Vieia>, Berk. — a, byphaa with conidia ; b, resting spore x 44. — Spluerotlieca Castagnei, Lev. — a, receptacle with appendages ; b, ascus with sporidia x EXPLANATION OF REFERENCES IN THIS WORE. Agri. Gas. N.S.W. Agricultural Gazette of New South Wales. Berk. Ann. N.H. Berkeley, M. J. B., in Annals of Natural History. Svo. v.d. Berk. Eng. Fl. Berkeley, M. J. B., in English Flora. Vol. v. part ii. Svo. 1837. Berk. Hook. Fl. Ant. Berkeley, M. J. B., in Hooker's Flora Antarctica, 4to. Berk. Outl. Berkeley, M. J. B. Outlines of British Fungology. Svo. London. 1S60. Bcrlese Icon. Berlese, A. N. Icones Fungorum. Imp. 8vo. Avellino. 1894. Bull. Soc. Myc. dc Ft. Bulletin de la Societe Mycologique de France. Royal 8vo. Paris. 1885-1905. Hull. U.S.A. Exp. Stn. Bulletins of the United States Experimental Stations. 8vo. Bot. Zeit. Botanische Zeitung. 4to. Berlin. 1843-55. Cav. App. Pat. Yog. Cavara, F. Appunti di Patologia Vegetale. Milan. 1888. Cooke Austr. F. Handbook of Australian Fungi, by M. C. Cooke. Svo. London and Melbourne. 1892. Cooke Hdbk. Handbook of British Fungi, by M. C. Cooke. 8vo. London. 1871. Cooke Illus. Illustrations of British Fungi. 8 vols. Roy. 8vo. London. 1881-1891. Cooke M. F. Introduction to Microscopic Fungi, by M. C. Cooke. 12mo. London. 1865, &c. C'ordct. Icon. Corda, A. Icones Fungorum hucusque cognitorum. 6 vols. fol. Prague. 1837-1854. Curr. Simp. Sj)l<. Carrey, F. Synopsis of simple Sphrcriae, in Transactions of Linnean Society. 4to. London. Ueut. Bot. Ges. Berichte der deutschen botanischen Gesellschaft. Berlin. 1882. ]>ub)i Hot. Call. Botanicon Gallicum, par J. E. Duby. 8vo. 1828-1830. Fekl. Sym. Myc. Symbolae Mj-cologicaj, par L. Fuckel. Svo. Wiesbaden. 1869- 1875. Gard. Chron. Gardeners' Chronicle from 1860 to 1906. London. Grevillea. Grevillea, a quarterly record of Cryptogamic Botany. Svo. 22 vols. 1872-1894. Grev. Sc. Crypt. Fl. Scottish Cryptogamic Flora, by Dr. Greville. 6 vols. Roy. Svo. 1823-1829. Grove Jowrn. Bot. Grove, W. B., in Journal of Botany. 8vo. London. Grove Syn. Bact. Synopsis of Bacteria and Yeast Fungi, by W. B. Grove, B.A. L2mo. 1884. Hart. & Som. Dis. Trees. Hartig A. and Somerville W. Textbook of the Diseases of T i o. London. 1894, Hussey. Hussey, Mrs. Illustrations of British Mycology. 2 vols. lto. 1847, &C. Jowrn. Board Agri. Journal of the Board of Agriculture. June 1905. Jowrn. Q.M.C. Journal of the Quekett Microscopical Club. 8vo. Jowrn. Boy. Ann. N"' . Jmirna] uf the Royal Agricultural Society. Svo. Jowrn. I:. U.S. Journal of the Royal Horticultural Society. Roy. Svo. Letell. Champ. Letellier, J. B. Jj. Figures des Champignons servant de suppla- nt aux pli ji Bulliard. Paris. 1842. Lev. Ann. Sci. Nat. Leveille in Annales des Sciences Naturelles. 8vo. Paris. isle, is is. EXPLANATION OF REFERENCES. XV Linn. Trans. Transactions of the Linnean Society of London. 4to. Marshall Ward, Timbers. Marshall Ward, Timber and some of its Diseases. London. 1889. Mass. B. F. British Fungi, Phycomycetes, and Ustilagineae, by Geo. Massee. Sm. 8vo. 1891. Mass. Fun. Fl. Massee, Geo., British Fungus Flora. 4 vols. Sm. 8vo. London. 1892. Mass. PI. Dis. Textbook of Plant Diseases, by Geo. Massee. Sm. 8vo. 1899. Nuovo Giorn. Bot. Ital. Nuovo Giornale Botanico Ital. Roy. 8vo. 1872-1891. Pers. Ic. Pict. Icones Pict® fariorum Fungorum, C. H. Persoon. 4to. 1803. Phil. Br. Disc. Manual of the British Discomycetes, by W. Phillips. Sm. 8vo. London. 1887. Plow. Brit. Ured. Plowright, C. B., Monograph of the British Uredineaa and Ustilagineae. 8vo. London. 1889. Prill. Mat. PI. Acjri. Prillieux, E., Maladies des Plantes agricoles et des Arbres Fruitiers, &o. Paris. 1895-1897. Quart. Journ. Micr. Sci. Quarterly Journal of Microscopical Science. 8vo. London. Sacc. Fung. Ital. Fungi Italici autographice delineati, P. A. Saccardo. Fol. Sacc. Syll. Sylloge Fungorum, P. A. Saccardo. 1882-1905. Seem. Journ. Seemann, B. Journal of Botany. 8vo. London. Soia. Fun. Sowerby, English Fungi. Fol. London. 1797-1809. Smith Field Crops. Diseases of Field and Garden Crops, by W. G. Smith. 12mo. 1884. Thaxton Bot. Gaz. Thaxton in Botanical Gazette. 8vo. Thiim. Pom. Thmnen, F. von. Fungi pomicoli. 8vo. Vienna. 1879. Trans. Br. Myc. Soc. Transactions of the British Mycological Society. 8vo. Trans. Crypt. Soc. Scot. Transactions of Scottish Cryptogamic Society. 8vo. Tubeuf Dis. Tubeuf, K. Diseases of Plants induced by Cryptogamic Parasites. London. 1897. Tulasne Fun. Carp. Sel. Tulasne, L. & C. Selecta Fungorum Carpologia. 3 vols, folio. Paris. 1861-1865. U.S.A. Dep. Agri. Rep. United States Department of Agriculture Reports. U.S. Journ. Myc. Journal of Mycology, Department of Agriculture U.S.A. Ward Dis. PI. Diseases of Plants, H. Marshall Ward, M.A. 12mo. London, n.d. Ward Ann. Bot. Annals of Botany, papers by H. Marshall Ward. Ward Trans. Boy. Soc. Marshall Ward in Philosophical Transactions of Royal Society. 4to. Fungoid pests OF CULTIVATED PLANTS Introduction. Some introductory remarks are necessary as an explanation of the main facts in the life-history of some of the principal parasites to be recorded, and thus prevent their subsequent repetition when each species is under consideration. Thus iteration will be avoided and space economised where there is so little to spare. One of the most rudimentary lessons to be inculcated is the known fact that parasitic fungi may be arranged under two types, each with a different mode of development, and each requiring a different mode of treatment. It is, at the least, essential to know to which of these types any given pest belongs before effectual steps can be taken against it. We have called these two groups the epiphytal and the endophytal. The former includes those fungi which establish themselves on the surface of the leaves, stems, or other green parts of living plants, and ultimately cause destruction by a kind of suffocation, and not by affecting, distorting, or absorbing the internal tissues. It is natural to suppose that it is this type of fungus pest which is most amenable to the application of fungicides, the object being to destroy the parasite without injury to the host-plant. We may give as examples the hop mildew and the oidium of the vine, both of which are to be kept in check by the application of sulphur. In these cases a white mould is developed in irregular blotches, or broad effused patches, over either or both surfaces of the leaves, the inferior stratum consisting of delicate interwoven threads, forming a mycelium, which attaches itself by means of haustoria, or suckers. From this mycelium arise the short fertile threads, which are mostly clavate. The upper portion is soon separated from the lower by a septum, at which it is constricted, and this upper cell, of an elliptical shape, becomes a conidium. Whilst this process is going on another septum is developed at an equal distance below the first, and another B 4 2 FUNGOID PESTS OF CULTIVATED PLANTS. conidium is differentiated. This process goes on until a chain of conidia is produced from the original hranch, the apical conidium being the oldest, and hence the first to separate itself from its companions, and so the rest fall away in succession until they form a thin stratum of conidia on the surface of the mycelium, in readiness to be transferred by wind or rain to other and healthy leaves (PI. III. fig. 54a.). Upon reaching its new location the conidium germinates by the production of a tube near its extremity, and tins germ-tnbe is the initial stage of a new mycelium. This is the asexual reproduction, by conidia, of the outturn condition of the Erysiphei, of which the ordinary European vine mildew and the Australian Erysiphc viticola are examples. Later in the season the threads of the mycelium produce a more complex form of fruit. A globose receptacle, of a yellowish colour at first, is to be seen here and there upon the white mycelium. It seldom exceeds a small pin's head in size, and ultimately becomes brown or black. The outer membrane, or perithecium, remains attached, and is soon surrounded with more or less distinct radiating flexuous threads or appendages, which vary accord- ing to the genera (PI. III. fig. 54 b). Internally the perithecium encloses one, two, or more hyaline pear-shaped sacs, or asci, which contain the sporidia. When mature the perithecia split irregularly, and the asci, with their sporidia, are ejected. Each sporidium is elliptical, hyaline, and capable of germination, the germ threads becoming a new mycelium. This is the ascigerous and probably sexual reproduction. The whole career of these epijrfiylal parasites is therefore external and superficial, and, if they can be destroyed by powdering or spraying, the leaves may recover their vigour ; but if not, by the destruction of the conidia or sporidia, or by their germination being prevented, the disease is held in check, and its extension to other leaves or other plants rendered impossible. The cultivator who possesses sufficient elementary knowledge of the fungi to determine whether the pests he has to deal with are of this nature is already in possession of the power to treat them effectually. Even the very crude method of picking off the diseased leaves and burning them will limit the area of infection. More important, and more destructive, are the endophytal parasites, which originate within the tissues of the host-plants, and only manifest themselves externally, when it is too late to save the plants. The " rot moulds" are of this kind, such as the Potato mildew, American Vine disease, Tobacco mildew, and many other devastating pests. They are called " rot moulds " because of the rotting of the leaves and stems sub- sequent to their attacks. Their scientific designation is Peronosporck and they have the habit and appearance of white moulds, but are para- sitic on living plants. Here, again, it is of the utmost importance to know something of their life-history, and methods of reproduction, before they can be combated with success. The mature mould, when it appears on the surface of a diseased plant, produces a profusion of spores, or conidia. Bach conidium is an elliptical colourless body, having a thin outer coating of membrane with fluid contents. These contents soon become granular, and at length collect at three or four centres, which condense and then become distinctly separated from each other by the owth of a special envelope. Ultimately the membrane of the mother FUNGOID PESTS OF CULTIVATED PLANTS. 3 cell is ruptured, and the three or four smaller bodies, which have been differentiated in its interior, escape, each one furnished at one extremity with a pair of delicate movable hairs, by means of which these little bodies, now termed zoospores, can swim actively in any thin film of mois- ture upon which they may fall. Possibly this film may be upon the leaf of a foster plant. In a short time all motion ceases and the zoospores come to rest, the pair of delicate cilia are absorbed, and a germinating thread is produced, the point of which seeks out and enters at one of the stomata of the sustaining plant. Having once obtained an entrance, the thread grows vigorously, and a little mass of threads, called a mycelium, is soon developed within the tissues, capable of spreading itself through the plant which it has infected. In. the next stage we discover that this mycelium has developed erect branched threads, which pass out through the stomata again into the external air, sometimes singly, sometimes in tufts. These are the fertile threads of the mould, which soon produce a single conidium at the tip of each of the branchlets, just like the original conidium whence the zoospores were developed (PI. VI. figs. 30, 78). "When fully matured each fertile thread produces a score or more of these conidia, which fall away when ripe, and then undergo transformation into zoospores, ready and active, prepared to pass through the same stages again, and indefinitely multiply the pest. This history represents the ordinary conidial fructification of the mould, by means of which it is passed from leaf to leaf, and from plant to plant, until the whole area is affected. How many of the minute conidia may be transported to a con- siderable distance by a breath of wind it is impossible to say, but it is known that they may be carried to any spot where there is sufficient moisture for the conidia to be differentiated into zoospores, and afterwards come to rest and germinate. This process takes place in summer and autumn, but there is yet another means by which the pest is disseminated in spring. The mycelium, which flourishes within the substance of the plant infested, is capable of producing larger globose bodies, chiefly within the stems, concealed from external view. These globose bodies secrete a thick envelope, mostly of a brownish colour, and after development they remain in a state of rest within the stems during the winter (PI. IV. fig. 70*). So that old stems of plants, which are infested with the mould during the autumn, conceal within themselves during the winter a large number of these "resting spores." As the old stems rot and decay, the resting spores are set free in the spring, and then a period of activity commences. The contents of these globose bodies become differentiated into a large number of zoospores, which ultimately escape by a rupture of the thick envelope, armed with vibratile cilia, and in all respects like the zoospores which are developed from the conidia. These active zoo- spores swarm over the damp soil, and are carried by the spring rains into proximity with the young seedling leaves of the new crop of host-plants ; then the cilia are absorbed, germination commences, the delicate threads of mycelium enter the nearest stomata, and infection results. In this way, in addition to the spread of the infection from conidia in summer and autumn, provision is made for an attack upon seedlings in the spring. It will be inferred that, in order to check the spread of these diseases, the b 2 4 FUNGOID PESTS OF CULTIVATED PLANTS conidia must be destroyed in the autumn to prevent their extension to healthy plants ; and the destruction of all rotting debris must be carried out during the winter, so as to extirpate all the concealed resting spores,, and thus prevent the infection of seedlings in the spring. From these details it will be evident that plants once attacked by cndophytal parasites are in themselves hopeless. No external application can destroy organisms which it cannot reach, or, if they could be destroyed, no manipulation can replace the disorganised tissues. Hence, then, all efforts should be directed towards the destruction of the conidia and resting spores, in order to stamp out the disease at its source and prevent the future infection of healthy plants. The application of spray- ing to plants apparently without disease would be done as a preventive, in order to destroy at once any germs which might be brought into con- tact with the foliage ; and the destruction of all infected material would limit the local sources of infection. With an intelligent appreciation of the objects which have to be attained, the cultivator may accomplish a great deal in the way of prevention, even though he may be helpless to effect a cure. It will be seen how much of this depends upon an accurate diagnosis of the disease. There are many other forms of endophytal parasites, and the life-history of some of these is still obscure. In the majority of them only a conidial fructification is yet known, and the internal tissues do not appear to be so absorbed and destroyed as in the case of the "rot moulds" ; but in such black moulds as the " Apple and Pear scab " the mycelium appears to be perennial, and produces a fresh crop of conidia each successive year. There is some evidence that this disease is deep-seated and hereditary, and if so it is doubtful whether any amount of external application will result in a perfect cure. The genus Ghrosiiorium includes many species which are very destructive, but often they seem to be localised, and the mycelium may not pass internally to other parts. This can only be ascertained by closer investigation. The little pustules on the leaves, and the fruits, are seated beneath the cuticle, where a cushion or stroma of compacted mycelium produces conidia, but without any enclosing mem- brane or perithecium. When the conidia are matured the cuticle is ruptured, and the spores escape to the surface, in many cases adhering in a somewhat gelatinous hkiss, which oozes out in the form of tendrils. In Buch cases it is evident that the application of some fungicide capable of destroying the vitality of the conidia will bo of service in preventing the spread of the disease (PI. 1. fig. 9). A large and important group of endophytes is that known as the Uredines, of which the common and disastrous " Wheat rust " or " Wheat mildew " is a familiar example. In the first instance, the host-plant pro- duces upon its leaves, in the spring, clusters of little cups, partly embedded in the substance of the leaf, which is usually tbickened and discoloured. These little cups constitute the "cluster cups," or iecidium form; the margin is usually white and fringed, and the interior filled with orange subglobosc spores, termed Acidiospores, produced in chains, but soon falling apart (PI. I. fig. 21 ). The recidiospores will germinate when mature and produce a thread of mycelium, which is capable also of producing secondary spores (fig. 1). Smaller bodies are also to be found in company, FUNGOID PESTS OF CULTIVATED PLANTS. 5 or in proximity, sometimes on the opposite side of the leaf. These have the form of minute embedded cells, containing very small hyaline spore- like bodies called spermatid, whilst the cells which contain them are spermogonia. What their function may be is as yet only conjectural, but they are nearly always present, and, presumably, not without a purpose. Later on in the summer the same leaves, or others, develop on either or both surfaces small brownish pustules, at first covered by the cuticle, but at length splitting irregularly and oxposing a powdery brownish dust- like mass of nearly globose spores, oach spore borne at first at the apex of a short hyaline thread, these threads arising from a cushion-like base of mycelium. These powdery spores constitute the " rust," or uredospores (PI. II. fig. 225), and with them ends the second stage of the fungus ; but how they are evolved from the first stage, or how they produce the third stage, is a mystery still. The third is held to be the complete or perfect stage, and the spores produced are teleutospores, or final spores. These teleutospores are more Fig. 1. — ^cidiospore germinating. or less elongated, divided by a septum across the middle into two cells, and supported upon hyaline sporophores or spore-bearing threads (PI. II. fig. 22c). They are produced in pustules similar to those of the uredo- spores, but often more compact, and are sometimes mixed with them. A few of the teleutospores will sometimes be found growing within the pustules of the uredospores. When the teleutospores are mature they do not always germinate at once, but a period of rest supervenes, and perhaps they may not germinate until the following spring, becoming, in fact, veritable resting spores. This is an important fact to be borne in mind by the cultivator. Each cell of the teleutospore is capable of sending out a perm tube through a special pore, and as this germ tube grows, the contents of the cell of the teleutospore passes into the germ tube, known also as the promycelium, and to the extreme end. Ultimately a septum, or division, crosses the tube and prevents retreat. One, two, or more additional divisions of the apical cell take place, and from the side of each of these newly constituted cells buds or processes appear, which gradually enlarge, and in time are converted into secondary spores, or promycelial FlNOOID PESTS OF CULTIVATED PLANTS. spores, into which some of the contents of the old spore pass, and these smaller hodies arc eligible for the production of mycelium, which is pre- pared to find an entrance into the leaf of some young and new host plant, and producing infection commence the cycle over again (fig. 2). Thus, then, we have in order of succession spermogonia, recidiospores, uredo- spores, and teleutospores, each of the three latter capable of producing secondary spores, but the last of all producing the promycelial spores which are the medium of reinfection, from the complete and perfect condition of the Puecinia. It may be mentioned, in passing, that the life-history in the genus Uromyces, where the teleutospores are only one-celled, is precisely similar. But all these stages are not always to be found associated together. The chain is not always perfect. In some cases the JEcidium only is Fig. 2. — Teleutospore germinating. known, with or without spermogonia; or in other cases only the uredo- spores are known ; or in certain cases only the teleutospores. In each of these instances the fungi are regarded as imperfect, or, at least, as imperfectly known ITredines. Besides these cases, in which a?cidiospores, uredospores, and teleuto- Bpores arc produced on the same species of host-plant, there is another group which those who have implicit faith in hetenecism contend produce the aecidiospores with spermogonia on one species of plant, and the uredospores and teleutospores on another and quite different species of host-plant. Let each lo persuaded in his own mind, as it will servo HO good purpose to cuter upon discussion here. There is another group in which only the spermogonia, uredospores, and teleutospores are known, and these all occur on the same host-plant. Here the .i-eidiospores are absent. In ;i fourth group only the ;ecidiospores and teleutospores are known, and these occur upon the same species of host-plant. The uredospores are wanting or do not produce pustules of their own. In the fifth group teleutospores only are known, so that both iecidio- pores and uredospores are absent, and the teleutospores only germinate after a period of rest. In another subsection only teleutospores are found, hut they germinate at once on arriving at maturity, without an FUNGOID PESTS OF CULTIVATED PLANTS. 7 intervening period of rest. Thus much it seemed necessary to explain, as it has some connection with the dispersion of the Uredines, and the steps to be taken in contending with them. It will be evident at once that the destruction of these clusters of teleutospores will minimise the spring infections, and hence that they should be well looked after and destroyed, either by effective fungicides, or by burning up all the dead leaves and stems of the foster plants known to have been affected. In this case, again, we must suggest the importance of acquiring some practical knowledge of the history and mystery of such plant parasites, if they are to be encountered and vanquished in their career of de- struction. In this connection we cannot omit alluding to the evidence, which is gradually accumulating, of the connection between those minute organisms the microbes, or Schizomycetes, and plant diseases. There are certain diseases which attack cultivated plants, and produce disastrous results which have long been a mystery, since, although the host-plants appeared to be suffering from the attacks of some insidious fungus disease, none of the usual external appearances could be detected. In several cases of this kind it has been affirmed, although not yet com- pletely confirmed, that the disease is caused by the presence of a minute bacterium or bacillus in immense numbers. There is no reason ana- logically why this should not be the case, and all the evidence seems to strengthen the probability ; but the suggestion is so recent and the inves- tigation so difficult that it would be imprudent to hazard any very decided opinion. Researches into a Vine disease in California, a Melon disease in some parts of the United States, and the very prevalent " Peach yellows " almost establish the fact that microbes are present in large numbers, and are hypothetically the cause of the disease. In reference to the disease of Cucumbers and Melons it has been claimed that the disease is accom- panied profusely by bacteria ; that the juice of diseased plants swarming with these organisms, when transferred to healthy plants, will inoculate them with the disease, which will make its appearance in three or four days; that seed watered with the juice of diseased fruits did not germinate, or only 25 per cent, germinated at all, and these soon decayed ; that the diseased juice when introduced into healthy stems and fruits of Tomato rapidly produced decay ; that young Tomato plants in proximity with diseased Cucumbers were all destroyed. Hence it is concluded that the disease in question is caused by bacteria, and may be transmitted to other plants by inoculation. If all this should be confirmed, then we shall have to deal with another class of plant diseases, of fungoid origin, which will require a different mode of treatment, and doubtless offer a stubborn resistance. From the foregoing observations it will be manifest that there are such broad distinctions between different groups of pestiferous fungi that they should not all be subjected to the same mode of treatment, and that the remedies which might be successful in cases of one kind would be powerless in another. Hence, then, modes of treatment must have a relation to the known character of the parasite. It follows from this that a certain amount of knowledge of the life-history and affinities of the parasite must precede any definite effort to counteract or destroy it, 8 FUNGOID PESTS OF CULTIVATED PLANTS. as in animal diseases an accurate diagnosis must precede treatment. Such being the case, it is important to consider what means can be employed to. diffuse the necessary information amongst cultivators, so as to enable them to determine the general character of the disease. This does not imply the specific identification of the fungus, which would be the work of an expert, but the general characteristics only, and especially whether the disease is caused by an endophyte or an epiphyte ; after this, presuming it to be an endophyte, whether it is related to the rot- moulds, the- forms of anthracnose, as represented by species of Glono- sporium, or to the "rusts" or Uredines. The cultivator in possession of the power to determine thus much for himself might easily learn what remedies have been most successful in similar cases, and apply them systematically with some hopes of success. Another important question cannot summarily be dismissed without consideration, and that is whether, and to what extent, heredity has to do with the dissemination of plant diseases. It is admitted that in the animal world certain diseases are hereditary. Can it be possible also that amongst plants there is any evidence to be found of the transmission of disease through the seeds to a succeeding generation ? On this point we have a few authenticated facts to submit, and then we have done. The first instance is a record of 1885 by W. G. Smith, where he states, as the result of his examination of Oat grains, that not only the mycelium but the resting spores of Corn mildew sometimes do exist within the grains of Corn when the Corn is planted ; that the fungus spores germinate at the same time as the grain ; and that the disease can be and potentially is hereditary.* There can be no doubt that some of these diseases are hereditary and can be transmitted through the seeds. A writer t says : " We had about 1,000 very fine plants (Sweet Williams) for blossoming next year, all raised from seed last summer, and in the autumn we noticed a few patches of the fungus {Puccinia Diantlii) and used Gishurst's compound and sulphur mixed with it as a solution, applying it with a syringe. We thought wo had destroyed it, but find that all the plants that are not dead are dying piecemeal, and there is not one that has escaped. We cannot grow one of these seeds from Japan ; immediately they are up in the seed-pans, under glass, they are attacked and destroyed." This view is also confirmed by a subsequent writer.J Upwards of thirty years ago a friend sent us specimens of infected Celery leaves, asking for the name of the pest, which was Puccinia A]>ii ; at the same time he stated that he had two separate stocks of Celery plants, and although l>oth were in the same garden, only one stock was attacked by the parasite. The seed which produced the infected plants was given to him by a person who had informed him since that all his plants were similarly affected. The seed from which the other plants were raised had been derived from another source, and not a pustule of the brand could be detected on the leaves ; and yet they had been transplanted and were growing in rows side by side. The conclusion is that the germs of the parasite were present in the seed * Card. Chron., kag. 22, 1885. f Gard. Chron., .Tan. 12, 1884, p. 57. \ Card. Chron., .Tan. 26, 1884, p. 120. .... * '■ ■■ ^ PESTS-FLOWER GARDEN FUNGOID PESTS OF CULTIVATED PLANTS. 9 which produced infected plants ; and if not, why did not all the plants suffer alike ? * The Rev. M. J. Berkeley records an instance in which plants of Pyracantha raised from seeds imported from Russia were all killed by a species of Fusicladium, whilst old plants of Pyracantha growing at the same place remained perfectly free from disease.t At the time when the Hollyhock disease was at its height a quantity of seedlings were found showing the disease in their seed-leaves : some of the seeds, or carpels, which had not been used were examined, and pustules of the disease were found developed on the outside, whilst similar traces of disease were found in seeds of Wild Mallows. J Cases need not be multiplied, since we contend that the above are sufficient to establish the fact that inheritance of fungoid disease must be taken into account in connection with the dissemination and perpetua- tion of these diseases. It only remains for us to intimate that in the following pages our first object has been to interest and instruct the cultivator in the simplest and most practical manner, which we believe would be best attained by grouping the pests together according to the nature of their hosts, rather than by following any purely scientific and systematic classification, which would assume considerable previous knowledge, and would be better left in charge of the expert. The grouping which has suggested itself is as follows : — Pests of the flower-garden ; ,, „ vegetable-garden ; ,, ,, fruit garden and orchard ; „ ,, vinery and conservatory ; „ ,, ornamental shubbery ; ,, ,, forest trees ; „ ,, field crops. PESTS OF RANUNCULACEOUS PLANTS. Although we have included descriptions of all the ordinary diseases of Ranunculaceous plants which are under cultivation, it must be remem- bered that there are also a large number of fungoid pests which infest wild and uncultivated plants of this order, some of which may at any time invade the flower garden and commence their ravages upon their cultivated kindred. Some limit being indispensable, we have been com- pelled to exclude the parasites of wild plants, except in those cases where they have been known to invade the garden. Black Hellebore Leaf-spot. Phyllosticta helleborella (Sacc), PI. I. fig. 1. The leaves of Hellebores are apt to become very much disfigured by parasitic fungi, of which many species are recorded, and amongst them the above-named, which made its first appearance in Italy. * Country Life, Sept. 19, 18G7, p. 88. t Gard. Chron., Oct. 28, 1848, p. 716. % Gard. Chron., July 1, 1882, p. 23. 10 FUNGOID PESTS OF CULTIVATED PLANTS. In the form which is found in Britain the foliage is disfigured hy large hlotches, or spots, on the upper surface, which are sometimes very irregular and angular in shape, without any distinct border or marginal line. At first they are blackish, but soon become paler and bleached in the centre, leaving the blackness around the edge. The spots are sprinkled with little black dots, like pin-points, which are the conceptacles, or perithecia, of the fungus, and contain the spores. Under the microscope these perithecia are blackish, minute, rounded, flattened bodies, with a pore or orifice at the apex, through which the spores escape, and are more or less immersed in the substance of the leaf. The sporules are oblong and colourless, minute (7 x 8 //), with two nuclei, and are produced on short stalks within the receptacles. In Italy this species is found growing in company with another fungus of a higher development, but resembling it in external appearance. In that case the spores are produced within delicate cylindrical cells, or asci, to the number of eight in each ascus, and the species is called Spharella Hermione, of which the above-named Phyllosticta is an imperfect condition. Hitherto there is no record of the perfect con- dition, or Spharclla, having been found in this country. At present, so far as we are aware, this parasite is confined to Italy and to isolated spots in Great Britain. If taken in the early stage of its appearance, and all the diseased leaves are removed, so long as the plants are otherwise in a healthy con- dition, they may recover. Failing this, the application of one of the copper solutions should be made. It may occur either on the leaves of Helleborus niger, viridis, or f &tidus. Sacc. Syll. hi. 201 ; Grevillea, xiv. p. 73, No. 403. Another and allied species, Phyllosticta atrozonata (Voss., f.), occurs on the leaves of II. viridis in Carniola. The leaf-spots are characterised by concentric zones, and the sporules are smaller. In France another species, Pln/llnsticta Helleboriana (Brum), occurs on the leaves of //. faiidus, in which the spots are smaller, rounded, and margined by a brown line, whilst the sporules are smaller still. In Italy the leaves of If. viridis are attacked by the angular, dry, pallid spots of Phyllosticta Helleboricola (Mass.), with very minute sporules. So thai altogether four species of the same genus of parasite have occurred on the leaves of Hellebore in Burope. Eellebobe Leaf-spot. Septoria Hellebori (Thiim.), PI. 1. fig. 2. This little-known parasite has on one or two occasions been found on the foliage of Helleborus niger in Britain, although first discovered in Austria. The spots on he Leaves are rather large and irregular, without any determinate margin, and of a brown colour. The spots are Bprinkled with the minute black dots, as in Phylk>8ticta. FUNGOID PESTS OF CULTIVATED PLANTS. 11 The principal difference, as revealed by the microscope, lies in the form and dimensions of the sporules, which, in the present instance, are long and thread-like (40-50 /< long). It has been found on II . niger and H.fcetidus in Austria, and in France, as well as in Britain. Fortunately it is so rare that experiments have not been made with remedies, but probably spraying would be useful. Sacc. Sytt. iii. 2H40 ; Grevillea, xiv. p. 102, No. 507. A similar parasite occurs in Italy on the leaves of 77. viridis, in which the spots are whitish and angular, circumscribed by a bhickish line, and is called Ascochyta Hcllebori (Sacc). The species in this genus resemble externally those of Phylluaticta and Septoria, but the sporules are different, since they are divided by a cross-partition into two cells. In this instance they are about 8 x 2 p.. Hellebore Blotch. Coniothyrium Hcllebori (Cooke and Mass.), PI. I. fig. 3. The leaves of the black Hellebore have been attacked in this country by a new parasite, which at present seems to be unknown abroad, and, fortunately, very little at home. The leaves are occupied by two or three dingy-brown spots, somewhat circular in form, but without any determinate margin. The minute dots of the p^rithecia are chiefly central, and more or less in concentric rings. Microscopically it differs principally in the sporules, which are oval (1-5 x 2-3 /.i) and of a pale brown colour, whereas in the other leaf- spots enumerated here the sporules are colourless. It is unnecessary to suggest remedies. Grevillea, xv. p. 108 ; Sacc. Syll. x. 574.8. Hellebore Smut. Urocystis pompholygodcs (Schl.). Urocystis Anemones (Pers.). This smut, which attacks Hellebore leaves, is also common on those of Anemone Hcpatica, Ranunculus, Pulsatilla, Eranthis, &c, and is here- after described as " Anemone smut." (See PL I. fig. 7.) Hellebore Leaf-mould. Ramularia Hcllebori (Fckl.), PL I. fig. 4. This delicate mould occurs in whitish patches on living, or fading, leaves of Hellebore in this country, and on the Continent, occupying either surface of the leaf. • The spots are rather small and of a circular form, becoming white, with a blackened or purplish margin- The mould appears to the naked eye only as a delicate frosting on the spots. Under the microscope small tufts of slender short threads arise from the mycelium, which pervades the spots (scarcely 20 /< long), and the 12 FUNGOID PESTS OF CULTIVATED PLANTS. conidia are produced singly on the tips of these threads. They are some- what fusiform or spindle-shaped, divided by a septum in the centre into two cells, and are a little longer than the threads which support them (24-30 x 4-5 /u), wholly colourless, but rather granular within, soon fall- ing away when mature. Spraying is generally effective in this class of parasites. The present species has been recognised in Italy, Switzerland, and Germany, as well as in Great Britain. Sacc. Fung. Ital. pi. 1013 ; Sacc. Syll. iv. 970 ; Grevlllea, xiii. p. 51. Hellebore Rot-mould. Pcronospora Ficaria (Tub), PI. VI. fig. 5. Many Ranunculaceous plants are liable to attack from a destructive mould of a similar kind to that of the Potato disease, and amongst them are the Hellebores. The foliage is attacked by the parasite, which soon takes possession of the entire plant. The external patches of the mould are effused, and of a dirty-white colour, looking like mealy blotches to the naked eye. When magnified the tufts of mould are seen to consist of erect fertile threads, which are from five to six times forked in the upper portion, the final branches, and those immediately preceding them, being curved and bent downwards, leaving obtuse angles. The conidia are borne singly on the tips of the threads, and are broadly elliptical, with a slight tinge of violet. Resting spores are produced, for the winter, upon the internal mycelium, the thick external coating being of a pale yellowish-brown. These resting spores are set free in the spring, by the rotting of the foster plant, and active zoospores, which are formed in the interior, then escape from their temporary prison and infect the young host-plants and per- petuate the disease. This disease is widely spread in Europe, being known in Britain, France, Germany, Belgium, Finland, and Italy, as well as in Bosnia and Lapland, and in the United States of America. Being such a complete endophyte, it is almost hopeless to attempt to save plants when once they are attacked ; external applications are of little avail. Sacc. Syll. vii. 835 ; Cooke M. F., p. 235 ; Garcl. Chron. July 7, 1888, fig. 2 ; Mass. B. F., p. 119. German Helleboke Rot-mould. Feronospora pulveracea (Fckl.). Tins disease, which attacks the foliage of Hellebores in Germany, has not yet been discovered in Britain. Externally it much resembles the British species, but the microscopical characters are somewhat different. The size of the conidia is represented as 25-30 x 18-22 p. Sacc Syll. vii. 875 ; Bcrlcse Icones, t. 52. FUNGOID PESTS OF CULTIVATED PLANTS. 13 Globe Flower Leaf-spot. Phyllosticta Trollii (Trail). This parasite has only recently been found on the leaves of Trollius europaus in Scotland. It forms irregular brown spots on the leaves, which are usually limited by the veins, and the receptacles, or perithecia, are scattered over the spots, on the under surface. The sporules, which are produced within the perithecia, are very minute (4x1 /<), obtuse at each end and colourless. Should it ever become aggressive, it would be well to try spraying with a copper solution. Trail, Trans. Crypt. Soc. Scot. 1889, p. 43 ; Sacc. Syll. x. 5003. The Globe Flower Brand (Puccinia Trollii, K.) has only been recorded in Italy, Switzerland, and Lapland. Two other leaf-spots are known to occur on the leaves of TrolHus, namely, Ascochyta Trollii, with two-celled sporules, only known in Siberia, and Scptoria Trollii, with long thread-like sporules, near Lake Lucerne in Switzerland. Aconite Diseases. Hitherto none of the special diseases which attack the Aconites have been recorded for this country. Septoria Napelli (Speg.) has occurred in Italy, and also Scptoria Lycoctoni (Speg.). JEcidium Aconiti-Napclli (DC.) and Uromyccs Aconiti-Lycoctoni (DC), the former in France, Germany, and Switzerland, the latter in Italy, Switzerland, France, Germany, Hungary, and Siberia, are not British, whilst JEcidium circinans is confined to Scandinavia. An Aconite white mould Bamularia monticola (Speg.) is also recorded for Italy. Larkspur Diseases. At present we have been spared the infliction of these diseases, of which Septoria Delphinella (Sacc.) is found in France. The mould called Cercospora Dclphinii (Thiim.) is still Siberian, whilst Puccinia Delphinii (Diel) is Californian. Anemone Rot-mould. Plasmopara pygmcea (Unger), PI. VI. fig. 6. This " rot-mould " is similar in character to that already described as occurring on Hellebore, and is found on the leaves of Anemone as well as sometimes on Aconite. The threads are often in bundles of two to six together, and are either simple or branched above, the branches are either simple or once or twice forked, the tips surmounted by from two to four short conical branchlets supporting the conidia. The latter are elliptical, of variable size (18- 25 x 15-20 /i), with the apex broadly and obtusely teat-like. In the interior of the plant the resting spores are produced from the 14 FUNGOID PESTS OF CULTIVATED PLANTS. mycelium. Those are globose (45-55 /x diam.) with a yellow-brown coating, or epispore, which is either smooth or minutely rugulose. The history and development of these rot-moulds are rather complicated, and may be found more in detail in the Introduction, p. 3. The distribution of this pest includes not only Great Britain, but France, Germany, Italy, Belgium, and North America. The remark on remedies under " Hellebore Rot-mould" applies with equal force to this species. Sacc. Syll. vii. 807; Cooke, M. F. 234, t, xv., f. 267; Bcrlcse Icones, t. 10 ; Cooke Hdbk. No. 1776 ; Mass. B. F. p. 112. Anemone- smut. Uroeystis Anemones (Pers.), PL I. rig. 7. This smut attacks the leaves and petioles of various allied plants, such as Anemone, Hepatica, Aconite, Hellebore, Ranunculus, Pulsatilla, and Eranthis, swelling and deforming them. To the naked eye its presence is very evident, as the leaves are blistered, and the petioles swollen, becoming paler in colour, until the distended cuticle bursts, and shows the mass of sooty spores, which are produced in profusion, and scattered over the plant as soon as they are mature, producing a most unsightly appearance. Under the microscope these spores are seen to be of a compound cha- racter, forming glomerules, or clusters, more or less globose. The central spores are dark brown, spherical, and compressed (18-16 /j) ; the peri- pherical or outer cells, to the number of about ten or more, are colourless and compressed at the sides (each glomerule about 26 ^ long). The tissues of the host-plant are traversed by mycelium. This pest is to be found in most European countries, in Asiatic Siberia, and in North America. It is always desirable to pick off and burn all infected leaves as soon as tin parasite makes its appearance, and thus it will probably be kept in cluck. Generally only one or two leaves are at first attacked ; but although the pest may appear year after year, it is possible to keep it under control if taken in time. Sacc. Syll. vii. 1901 ; Cooke 21. F. 91, 232, t. ix., f. 183, 184 ; Gard. Chron. Sept. 30, 1876, fig.; Floicv. Brit. Ured. 288; Cooke Hdbk. No. 1511 ; Mass. B. F. p. 188. Anemone Cluster-cups. Mcidium punctatum (Pers.), PI. J. fig. s. The leaves of the garden Anemone are liable to attack from this i ' cies of cluster-cup which is generally believed to be a distinct species from the Mcidium Anemones (Pers.), which attacks the foliage of the Wood Anemone, and has colourless a'cidiospores. The eups are scattered over the leaves, somewhat uniformly, whilst the leaves arc much thickened by the mycelium. The cups are llattened, and semi-immersed, with a torn, rather yellowish margin. The lobes are larger than in the common wild species, and are often not more than four to each cup. The secidiospores are almost globose (16-23 /*) and of FUNGOID PESTS OF CULTIVATED PLANTS. 15 a brownish -yellow colour. The foliage is very much distorted when attacked by this parasite, which has a facility for spreading rapidly. Hitherto it has not been demonstrated that there are associated with this species, as with many others, a Uredo form and a Puccinia form, but it appears to be complete in itself. It has been found, besides Great Britain, also in France, Italy, Germany, and Belgium. Pick off affected leaves and spray with copper solution to destroy scattered spores. Sacc. Syll. vii. 2705 ; Cooke M. F. ii. 194 ; Cooke Hdbk. No. 1601 ; L'lmrr. Brit. Ured. p. 268. Another cluster-cup [Moid, leucospcrminn) with whitish jecidiospores and the accompanying rust {Puccinia fused) is found on Wild Anemone. Anemone Peziza. Sclerotinia tuberosa (Hedw.). It has long been known that certain long-shaped bodies, resembling Anemone roots, are to be found amongst the roots of the Wood Anemone, and are called sclerotia, which represent a kind of compact fungus X -KJO Fie. 3.— Sclerotinia tobekosa, natural size; As. is and Spobidia x 400. mycelium. It is more than probable that they were originally true Anemone roots converted into sclerotia, as the grain of Rye is changed into ergot. In 1893 evidence was given (Gard. Chron. p. 75) that these sclerotia have appeared also amongst garden Anemones. \n form and size they resemble the rhizomes of Anemone, but are 16 FUNGOID PESTS OF CULTIVATED PLANTS. harder and more compact, and of a different internal structure and composition. Ultimately, and in autumn, these sclerotia send up one or more fleshy stems to the surface of the soil, where the apex at length expands into a cup-shaped form, half an inch or more in diameter, and of a brownish colour, with a fleshy substance, easily broken up with the fingers. These cups are such as were formerly called Peziza, but now Sclcrotinia, because developed from a sclerotium (fig. 3). The interior of these cups is fertile, and a thin section shows, under the microscope, that it is composed of long cylindrical cells called asci, placed side by side. Each of these asci contains eight spores, or sporidia, uncoloured, and elliptical in form (15-17x6-7//): when mature these spores are ejected like a cloud of fine dust. Collect the Peziza form in the spring to prevent diffusion. Sacc. Syll. viii. 797 ; Gard. Ckron. May 28, 1887, p. 712, fig. 137; ib. July 15, 1893, p. 75 ; Mass. PL Bis. p. 157. Anemone Leaf- spot. Septoria Anemones (Desm.). We have no record of this leaf-spot hitherto on any but uncultivated Wood Anemone, and upon this it is common. Hepatica Diseases. At least two diseases of Hepatica are known on the Continent, but at present have not made their appearance in Britain. These are the cluster-cups, JEcidium Hepatica (Beck), and the leaf-spot, Septoria. Hepatica (Desm.). Sacc. Syll. iii. 2830, vii. 2706. The May Apple leaf-spot {Phyllosticta Podophylli) has occurred in gardens on the leaves of Podophyllum pcltatum, although of little importance [Grew xiv. 7i). COL QMBIN E ANTHPvACNOSE. Gloeospc riii nt Aguilegia (Thiim.), PI. I. fig. 9. The leaves of living Columbines are subject to the attacks of a minute fungus of a destructive kind, but hitherto little known in this country. in this case the little dots make their appearance on both surfaces, clustered together on discoloured spots. The spots are rather large, irregular, and of an ochraceous colour, with a broad brown margin, caused by the internal mycelium which destroys the vitality of the leaf. The dots represent cavities in the substance of the plant, which contain the numerous conidia, or spores : these are at first borne on short stalks, but soon liberate themselves, and are expelled in a kind of tendril from the orifice in the cuticle. In this species the conidia are elliptical, without any division (12-15 x 5 ft) and colourless. FUNGOID PESTS OF CULTIVATED PLANTS. 17 The species was first discovered in Siberia, but has recently been found in gardens in this country, although hitherto there has been no record of its appearance in Continental Europe. There is no accounting for the manner in which some of these parasites diffuse themselves, so as to suddenly appear, and perhaps as suddenly disappear, in localities far remote from each other. Another species, Glaosporium Martianoffianum, with the conidia twice as large, has also been found in Siberia on the same host-plant. Diluted Bordeaux mixture checks the disease. Sacc. Syll. iii. 3660 ; Grevillea, xiv. 123. Columbine Leaf-spot. AscocJiyta Aquilegice (Roum.), PI. I. fig. 10. One kind of leaf-spot has been found in this country on Columbine leaves, and has probably migrated from France, where it was first discovered. The spots on the leaves are somewhat rounded and nearly white (tj-1 m. diam.), with a dusky margin, dotted towards the centre of the spots with the minute perithecia. The conidia are narrowly elliptical, with a brownish tint, and are divided by a septum across the centre into two cells. If troublesome, try spraying with one of the fungicides. Sacc. Syll. iii. 2191. Another leaf -spot has been found in France on Columbines, Plujllo- sticta aquilegicola (Br.), with brownish spots and small continuous conidia (8x2 /<). Another occurs in Italy, in which the spots are whitish, with a broad brown margin, but the conidia are long and threadlike. This is called Septoria Penzigii. The purple spot parasite has also been found in Italy. Septoria Aquilegice has rather longer threadlike conidia. The North American leaf-spot is perhaps different. A tufted mould, seated on purple-brown spots, is known in the United States as Cercospom Aquilegice, of which the conidia are very long (140-300 x 5-6 fi). Columbine Cluster-cups. JScidium Aquilegice (Pers.). These cluster-cups have often been regarded as a variety of the Ranunculus cluster-cups, but there are other writers who contend that they constitute a distinct species, without any indication of either uredospores or teleutospores being affiliated thereto. They occur collected in clusters upon round or irregular yellow spots, with a violet-brown margin, on leaves of Columbine. The cups are shortly cylindrical, on the under surface, seated upon ;i thickened cushionlike base. The aecidiospores are compressed and angular (16 30 x 1-1-20 /<), orange in colour, and distinctly warted. They have been known for many years as occasional occurrences in c 18 FUNGOID PESTS OF CULTIVATED PLANTS. Britain, and their geographical distribution includes France, Switzerland, Germany, Finland, and Siberia. \. ver likely to cause sufficient trouble to call in the aid of fungicides, better to pick off the diseased leaves if the cups appear. Sacc. Syll. vii. 2710 ; Pets. Ic. Pict. iv. t. 28, f. 4 ; Cooke Hdbk. No. 1615a ; Ploicr. Brit. Ured. 263. P.eony Leaf-spot. Phyllosticta Paonia (S. & Sp.), PI. I. fig. 11. Pa?ony leaves are subject to several kinds of leaf spot in different countries, but only the above has at present been recorded for Britain. This scarcely deserves to be called a " leaf-spot," since the spots are obsolete, and the rather large perithecia are scattered, like little black dots, over the leaves. The conidia are elliptical, with two nuclei (10 x 5 yu), and have a slight tinge of olive. The greatest harm that the majority of these leaf -spots do to the plants is to disfigure the foliage. In general they may be kept in check by spraying and picking off the infested leaves. Sacc. Syll. iii. 200. Three other species of Phyllosticta are recorded as producing leaf- spots on Pa^ony. These are Plujllosticta Moutan and Phyllosticta baldensis in Italy, and Phyllosticta Commonsii in North America. Other leaf-spots are produced by species of Septoria, with long thread- like conidia, such as Septoria Pceonia in N.-W. Europe, and Septoria macrospora in Italy. Septoria Martianoffiana is only known in Asiatic Siberia. P.eony Rust. Cronartium Pceonue (Cast.), PI. I. fig. 12. A peculiar kind of rust, not very common but occasionally appearing in gardens, on P.-eony leaves, chiefly on the under surface, is the above, which has been known for very many years. The pustules are small, and collected together on paler spots, but with none of the bright yellow or rusty colour peculiar to most of the plant rusts. The uredospores are enclosed in a kind of peridium, or volva, and are either ovate, or elliptical, and spiny (20 30 x 15 30 fx). From the centre of the spore mass arises a compact column composed of the brown teleuto- spores, or final spores, many of which commence to germinate while still attached to the foster plant. The long rlexuous columns (2 m. long) give a peculiar appearance to this parasite, making it look rather like a colony of worms or larvje upon the leaf, commonly extending over a consider- able surface. It has very little of the general appearance of a I'redine, and Would rather puzzle the inexperienced. It is found throughout the greater part of Europe and in Asiatic Siberia. No successful experiments recorded, and the presumable a'cidiospores are unknown. Sacc. Syll. vii. 213!J; Mass. PL Bis. p. 285; Cooke M. /•'., 215; Phwr. Brit. Ured. 25 1. FUNGOID PESTS OF CULTIVATED PLANTS. 19 P.eony Brown Mould. Cladosporium Pceonue (Pass.), PL I. fig. 13. This mould was first found in Italy by Professor Passerini in 1876, and has since made its appearance in this country. It forms broad chestnut-brown spots on the foliage, which ultimately turn black. The threads are short and unbranched, nearly straight, and erect, divided transversely into joints, and springing from an abundant creeping mycelium. The threads bear at their tips the very variable conidia or spores, which are commonly one- or two-septate, and sometimes two or more are attached in a short chain (15- 22 x 6 n). ■ Although found upon still living, but faded, leaves, it is rather uncer- tain whether it should be regarded as a destructive pest. Many species of Cladosporium are very common on decaying plants, and for the most part are simply saprophytes. The Tomato mould (Cladosporium) is nevertheless a destructive parasite, and possibly others may become so. Spray with dilute potassium sulphide solution. Sacc. Syll. iv. 1729. Another brown mould, of a different character, Cercospora variicolor, with long slender conidia (35-50x3^), has been found on Pfeony leaves in the United States. This is a true parasite. Drooping P.eony Disease. Botrytis Pceonia (Oud.), PI. VI. fig. 14. This white mould appear rather suddenly upon what appears to be healthy-looking plants, causing them before the time of flowering to become limp, the stem droops, and at length the plant dies. The mould may be detected on the stem of a diseased plant like a delicate white mould on the blackened and shrivelled surface. The threads terminate in somewhat globose heads, which bear a profusion of colourless elliptical conidia, or spores (16-18 x7 fi). Later on small black sclerotia, which are compact masses of hibernating mycelium, will be found in the tissues, both above and below the ground. It is presumed that these sclerotia remain in the soil until the suc- ceeding spring, when they may start into new life, as some of these sclerotia do, under the form of a minute Peziza. This threatens to be a troublesome disease, and should be encountered at once should it appear. All infected parts should be destroyed, so as to prevent hibernation of the sclerotia. Mass. PL Dis. 157 ; Gard. Chron. Aug. 13, 1898, fig. 32. Clematis Diseases. The cultivated species of Clematis have hitherto been remarkably free from fungoid pests, whilst our common hedgerow species has two or three enemies. One or more of these may at any time make their appearance in the garden, especially those in which Clematis Vitalba may have secured a place. Hence we enumerate, incidentally, the; . 22 FUNGOID PESTS OF CULTIVATED PLANTS. Poppy Rot-mould. 1'ivonospora arborescens (Berk.), PL VI. fig. 15. 'I'll is is the principal pest of the Poppy family, and occurs on the leaves of the Opium Poppy, as well as on those of some uncultivated species. It was first described by Berkeley in the Journal R.H.S. forty years ago. It appears as a white mould, in patches, on the under surface of the leaves. The fertile threads are erect, slender, and divided from seven to ten limes, in the upper portion, in a furcate manner. The branches are more or less flexuous and spreading, gradually attenuated, so that the final branches are very thin, somewhat curved, and pointed. The conidia are almost globose (15-22 x 18-18 /<), with a tinge of violet. In the autumn resting spores are produced upon the mycelium, within the tissues of the host-plant, and these are globose, with a striate brown envelope or coating. The production of active /.oospores, and their aid in the perpetuation of the species, follow the type of the other species of rot-moulds. See Introduction, p. 2. This species has been found in France, Belgium, Germany, and Italy. Spraying as a remedy can be of little use in so deep-seated an endophyte, but all parts of diseased plants should be burnt so as to destroy the resting spores. Cooke Hdbk. No. 1785 ; Journ. Boy. Horl. Soc. i. p. 31, t. 4, f. 24 ; Sacc. Syll. vii. 836 ; Cooke M. F. p. 217 ; Bcrlcsc Icones, t. xliii. ; Mass. B. F. 120. A black mould, Heterosporium Eschscholtzice, is found on Esch- scholtzia leaves in California. Mignonette Disease. Cercospora Reseda (Fckl.), PL I. fig. 1G. This fungus is rather common on the wild species of Reseda, and jometimes proves destructive to the cultivated Mignonette, causing dusky- brownish patches upon the foliage. To the naked eye the blotches on the leaves seem to be minutely velvety from the threads of the mould, and without definite margin, but it spreads rapidly from plant to plant. The threads are short (50 ^ long) and densely crowded together, i plate, and brownish in colour. The conidia are produced at the apex of the threads singly, and are very long and flexuous (100-140x8 /i), attenuated gradually upwards, and divided by numerous (four to five or more) transverse partitions, or septa ; they are also slightly coloured. It has been observed in Britain, Germany, Italy, the United States, and Australia. Spraying with dilute Bordeaux mixture has been recommended. Sacc. Syll. iv. 2092; Mass. PL Bis. p. 319; U.S.A. Depart. Agric. Rep. 1889, with plate; Orevillea, ill. 182 ; Jov/rn. J:. U.S., wix., p. 766. A rot-mould, Perm crispula, has been found on leaves of Eeseda luteola in the Rhine Provinces, and may at any time attack the Mignonette, should it appear on our uncultivated species of Reseda. FUNGOID PESTS OF CULTIVATED PLANTS. 23 PESTS OF VIOLET AND PANSY. Considerable anxiety is manifested by those who grow these plants extensively as to the prospects of the future, with the increasing number of Violet diseases which we are about to enumerate. Nevertheless it must still be remembered that quite a number of fungoid pests are known as affecting this family which have not yet made their appearance in the garden, but are common on uncultivated representatives. To be fore- warned is to be forearmed, and all prospect of contagion from infested wild plants should always be held in consideration. For this purpose we have thought it prudent to give incidental notices of the diseases to which uncultivated plants are liable, as well as some affecting cultivated species, which have not as yet invaded our shores. Violet Leaf-spot. Plnjllosticta Viola (Desm.), Plate I. fig. 17. This spot has occurred on the leaves of Viola odorata and Viola tricolor in various parts of Europe. It disfigures the foliage, but seems to have but little influence on the flowering. White rounded spots are formed on both surfaces of the leaves, several spots occurring on the same leaf, and then occasionally coalescing and forming irregular blotches, but with a definite margin. The receptacles, or perithecia, are very minute, resembling little black dots just visible to the naked eye, scattered over and immersed in the bleached spots. The sporules, or conidia, are produced within these receptacles, escaping when mature by a pore at the apex. In this instance they are cylindrical and straight (10 /u long), rounded at the ends and colourless, oozing from the mouth of the receptacle in the form of a whitish tendril. - The variety on the Pansy has rather smaller sporules (7 x 3p). This pest is known in France, Belgium, Italy, and Great Britain, as well as in Australia. If troublesome in gardens fungicides should be resorted to in order to prevent spreading. Sacc. Syll. iii. 203 ; Cooke Hdbk. No. 1352 ; Grevillea, xiv. 73, No. 404. Another species, Phyllosticta Liberia (Sacc), with blackish leaf-spots and very minute sporules, occurs on Sweet Violet leaves in France and Belgium. Ascochyta Violce (Sacc.) has badly attacked Violets in this country. See Gaul. Chron. Nov. 5, 1904, p. 328. Dog Violet Leaf-spot. Septoria Violce (West.), PI. I. fig. 18. This minute endophyte has occurred upon the leaves of several species of Viola, and especially on the Dog Violet, V. canina and V. sylvestris, probably also on the Sweet Violet. Pale bleached spots are formed on the leaves, circumscribed by a *24 FUNGOID TESTS OF CULTIVATED PLANTS. reddish-brown line. Upon the upper surface of these rounded bleached spots, but immersed in their substance, are numerous minute dotlike brown receptacles, or perithecia, so small as to appear like pin-points to the naked eye. The sporules, contained within these receptacles, are long and thread- like, sometimes straight and sometimes flexuous, and colourless, escaping when mature by a pore at the apex. It may be remarked here that the ordinary leaf-spots are produced by fungi of three genera, all very much alike in external appearance, but differing in the form of the sporules. In Phyllosticta they are very small, about twice as long as broad, more or less, and undivided. In Ascochyta the sporules may be similar, or larger, divided across the centre into two cells. In Se2)toria the sporules are generally very long, and threadlike, sometimes with a row of nuclei, or several transverse divisions. The above-named species is found in Britain, Belgium, and Italy. If troublesome, spraying may be useful to check it. Sacc. Syll. iii. 2811 ; Grevillea, x. 48. Septoria riolicola is found on leaves of V. bifiora in Switzerland and Germany, and Septoria hyalina on two or three species of 1'iola in North America. Violet Axtukacnose. Gloeosporium Yiolce (B. and Br.). Some years ago the Eev. M. J. Berkeley received some leaves of Viola odoraia from Scotland, with a parasite which he briefly described under the above name. The leaves were disfigured by one or two pallid spots, which concealed minute cavities scattered over the surface. In these cavities were produced minute sporules, or conidia, which were expelled through ruptures of the cuticle when moist, oozing out in little orange gelatinous masses, and spreading themselves over the surface of the leaf. Thus far goes the description, and we have since seen the only specimens which passed through Berkeley's hands, but fail to hud any trace of conidia or sporules on the discoloured spots ; and as the parasite has never been found since, it must remain uncertain or doubtful. Grevillea, \i. 120 ; Sacc. Syll. iii. :\(W>h. Another species of Anthracnose, which might possibly be the same, has been found on Violet leaves in Italy, and called Marsonia Viola (Pass.), the difference being that the spots are of a chestnut colour, and the sporules, which are narrowly elliptical (16-18 x 5 /i), are divided across the- centre into two cells, the only distinction between Glcso- sporium and Marsonia being that in the latter the sporules are bicellular. Sacc. Syll. iii. 1086. Violet Smut. Urocystis Viola (Fischer), PL I. fig. li). In some gardens, for the past century, the Violet smut has been more or less of a nuisance, disfiguring the Foliage and weakening the plants. PESTS FLOWER GARDEN. FUNGOID PESTS OF CULTIVATED PLANTS. 25 The leaves are blistered and distorted, chiefly along the midrib, and the petioles become swollen and gouty, usually twisted and pallid. Later on these pustules split irregularly down the centre, and expose a mass of blackish spores, like soot, which are scattered over the leaves. These spores are complex, like those of the smut on Hellebore and Anemone, and consist of irregular rounded balls (82-50 x 20-45 /<) compounded of a number of smaller cells, the central ones being dark brown (10 x 17 /* diam.) and from one or two to six, angular by com- pression, while the outer ones, or those of the circumference, are colourless and somewhat hemispherical, but they do not germinate (6-10 ft diam.). When the coloured spores germinate they give origin to a short thick thread (promycelium) into which the coloured contents of the spore pass. From the end of this thread five or six fusiform secondary spores are produced. Sometimes the secondary spores will germinate and produce tertiary spores. This parasite is so deeply seated that fungicides are of little avail. All that can be done is to pick off all the diseased leaves, as soon as they appear, and burn them, so as to prevent the germination of the spores and the spreading of the disease. It is certainly well known in France, Germany, and Italy. Sacc. Syll. vii. 1905 ; Cooke M. F. 92, 232, t. ix., f. 185, 186 ; Mass. B. F. 189 ; Plowr.Brit. Urea 1 . 288 ; Cooke Hdbk. No. 1538 ; Tubeuf, Dis. 317. fig. 174 ; Gard. Chron. Sept, 30, 1876. Violet Rust. Puccinia Viola (Schum.), PL I. fig. 20. The Violet rust is so widely diffused, and so general on wild plants, that it is fortunate it is not found oftener in the garden than it is. Like many others of its kindred it is developed under three forms or stages, the earliest being the cluster-cups, and afterwards the Uredo and the Puccinia. For practical purposes it is better to treat them as distinct diseases, without reference to their genetic connection, or, at least in so far as the cluster-cups are concerned, their entirely different appearance to the ordinary observer. The pustules of the Uredo, and afterwards of the Puccinia, are scattered over the surface of the leaves, the former of a rusty-brown colour, and the latter dark brown, nearly black, breaking through the epidermis. The uredospores are powdery, and are produced in little pustules on either surface of the leaves. Individually they are nearly globose, and rough with short spines (21-26 x 17-23 ju). The teleutospores, or final spores, are darker in colour, and are pro- duced in similar pustules, often mixed with those of the Uredo. They have the usual Puccinia form, with a central partition dividing them into two cells (20-35 x 15-20 fi). When mature these teleutospores are capable of germinating from each cell, the threads so produced developing towards their apex two or three secondary spores, which are simple and much smaller than the primary spore. The life-history and development are very similar in all the species of Puccinia. See Introduction, p. 5. 2G FUNGOID PESTS OF CULTIVATED PLANTS. The present is a widely diffused species, and is known, not only in Britain, but also in France, Belgium, Germany, Switzerland, Italy, Austria, Finland, Asiatic Siberia, North America, and Patagonia. It is doubtful whether fungicides are of much service with such deeply seated endophytes as Puccinia, although it was affirmed, during the greatest prevalence of the Hollyhock Puccinia, that spraying with Condy's fluid was decidedly advantageous. Sacc. Syll. vii. 2163 ; Cooke M. F. 102, 210 ; Ploicr. Brit. Ured. 152 ; Cooke Hdbk. No. 1502. It should be mentioned here that another species of rust has been found, in Britain and Germany, on the leaves of Viola palustris, and named Puccinia Fergussonii, in which the pustules are clustered together in large rounded patches. The teleutospores are smooth and rather deformed (20-30x13-20/0 ; no uredo spores have at present been found (Grevillea, iii. p. 179). Yet another species (Puccinia hastata) occurs on the leaves of Viola hastata in the United States, with much larger teleutospores (35-40 x 20-25 /<) and smooth globose uredospores. A third species (Puccinia alpina) is found on leaves of Viola biflora in Germany. Switzerland, Italy, and Lapland. The teleutospores are longer than in any other of the species (30-52 x 17-23 /<), with the surface finely granulated. Violet Clustek-cups. JEcidium Viola (Schum.), PI. I. fig. 21. In these modern days the above cluster-cups are treated as a stage in the development of Puccinia Viola, but their general appearance is so distinct that for general purposes we prefer to treat them as a separate disease. All the green parts of the Violet plants are liable to be invaded by this parasite. The cups are disposed in groups or clusters, seated on the leaves upon yellowish spots. The margin of the cup is white and torn into irregular teeth, exposing the bright orange acidiospores (1G-21 x 10 in //), which, as usual, are produced in chains, being separated and dispersed when mature. The area of distribution corresponds with that of the Violet rust. It is not sufficiently common to have originated any experiments with fungicides. Scattered Cluster-cups. Puccinia cegra (drove), PI. II. fig. 22. Another species of cluster cups was discovered in 187<>, principally on the stems, hut also on the foliage of Viola comuta. The cups are feu and scattered (.Kcidium depauperans) and the ;ecidiospores are also orange. In 1HH:5 the corresponding Uredo and Puccinia were found, which were described under the name of Puccinia cegra. They have hitherto only been found in Britain (( rrevillea, v. p. 57). A species of cluster-cups lias also been found on wild Violets in the United St.-ltes. FUNGOID PESTS OF CULTIVATED PLANTS. 27 Sacc. Syll. vii. 2174; Cooke Hdbh. No. 1626; GarcZ. Ghron. 1876, 175, 361, fig. 72 ; Cooke M. F. 198 ; Grove Journ. Bot. 1883, p. 274 ; Ploicr. Brit. Ured. 158. Violet Hot-mould. Pcronospora Yiolce (P. Bary), PI. VI. fig. 24. Amid all the vicissitudes of the Violet crop it has hitherto suffered little serious injury from the rot-mould, which is of close kindred to the Potato disease mould. It has appeared, and is not uncommon, on wild plants, and has recently invaded the Violet and Pansy under cultivation. The tufts of the mould are effused on the foliage, and although white are not particularly conspicuous ; the threads are collected in little bundles, growing erect, and are many times divided in the upper portion into forked branches, with the final branchlets awl-shaped and bent backwards. The conidia are elliptical, growing singly at (22-27 x 15-19//) the tips of the branchlets, but with a slight tinge of violet in their colour. It is assumed that resting spores are produced, as in other rot -moulds, but they have not yet been detected. (See Introduction, p. 3.) Plenty of air, and not too much water, retard the spread of the disease. Another rot-mould (Peronospora megasperma) has been found on Viola tricolor in the United States. Sacc. Syll. vii. 838 ; Bcrlese Icones, t. xlii. ; Mass. PI. Dis. 80 ; Cooke M. F. 235 ; Grevillea, iv. 109 ; Mass. B. F. p. 121. Violet White Mould. Bamularia lactea (Pesm.), PL I. fig. 23. This common little white mould on Violet and Pansy leaves does not much trouble the cultivator, since it has preference for the wild plants. White orbicular spots appear on the leaves, circumscribed by a brown line, three or four spots being usually present on one leaf. The mould gives a mealy appearance to the spots, as if they had been powdered with flour, and principally on the under surface. The mould itself is a very simple structure, consisting of rather twisted short threads (30-60 p. long), without branches, bearing at their tips the oblong or spindle-shaped conidia (8-10 x 2-3 fi). Occasionally two or three of the conidia will be met with attached to each other, end to end, so as to form a short chain. It has been suspected that many of the species of this genus of moulds are only the naked conidia of some higher form of fungus, as has been proved in a few cases. The present mould is known, not only in Britain, but also in Fiance, Germany, Bohemia, Austria, and Italy. It seems to be amenable to fungicides if taken in time. Sacc. Syll. iv. 979 ; Journ. Boy. Agr. Soc. lxi. (1900), p. 735 (sub Ovularia lactea) ; Journ. B.II.S. xxvi. (1901), p. 198 ; Grevillea, iv. p. 109. Another species, Bamularia ogre's tis, with larger and sometimes septate conidia, has occurred on \ 'iolet and Pansy leaves in Italy. 28 FUNGOID PESTS OF CULTIVATED FLA NTS. American Spot Disease. Altemaria Viola (Gall.), PL II. fig. 25. There is very little doubt that this disease has made its appearance in ibis country, and is capable of doing considerable damage. It occurs principally on the leaves, commencing with small yellowish spots, sur- rounded by a narrow rim ; sometimes they spread till they occupy the whole leaf. Most of the spots are free from fungus spores, with scarcely any indications of mycelium. Spores are developed in a saturated atmo- sphere after twenty- four hours. The spores are borne in chains, or darkish-brown threads, which rise from the diseased surface. They separate easily, and can be transported freely to other and healthy leaves. These spores, or conidia, are club- shaped, or flask-shaped, divided by transverse as well as vertical septa, so as to be muriform (40-60 x 10-17^), somewhat olive in colour. Hitherto known only in the United States and in Britain, it is undoubtedly a dangerous pest. At present no effective remedy has been discovered. Fungicides have produced little or no effect. Suggestions are made as to prevention, rather than cure, by giving careful attention to the production of vigorous, healthy plants. Healthy plants inoculated with the fungus spores soon produced the disease. U.S.A. Dep. Agric. Bull. 23, 1900; Journ. ll.H.S. xxvi. (1901), p. 246, pp. 191-3 ; xxvi. 1902, p. ccxxii. Italian Violet Black Mould. Macrosporium Ywlce. A black mould, under the above name, of which we have no descrip- tion up to n<>\\. is reported to be destructive to Violets in Italy. At the time of going to press we have seen Violets with the leaves in a bad condition, but there is no evidence that such condition has been caused by a parasite. The tissue was entirely bleached and dead over a large portion of the surface, commencing at the margin, and extending inwards, and not interfoliary. Cultivators are of opinion that it is due to external circumstances, which is most probable. All the dead spots seen by us become occupied by tufts of black mould, which are not present when the fading commences, but occur only on the dead tissue, and hence it is probably a saprophyte. The moulds are of two kinds, growing in company, forming small dark olive tufts, and not becoming continent. The earliest form is a Cladosporium, with slender unbranched septate threads of a pale olive and rather Lon The conidia- at first continuous, then uniseptate, at Length hi- or tri-septate (18 30 x 7 /<). The other mould, which appears mixed with the former, is a Macro- sporium resembling M. sarcinula, with delicate deciduous threads and BOmewhat cubical conidia (30 35x25 30 /<)• Truncate at the ends and but slightly constricted. The septa, Longitudinal and transverse, divide the conidia into quadrangular cells, mostly in three irregular rows, and of a darker olive-brown than the Cladosporium, FUNGOID PESTS OF CULTIVATED PLANTS. 29 Further investigation is advisable, but it certainly is not the Italian species. Gard. Chron. 1902, April 12, p. 265. Violet Black Moulds. Gercospora Viola (Sacc), PI. II. fig. 20. This destructive genus of black moulds has no fewer than six repre- sentatives, which attack members of the Violet family. They form spots on the leaves, and develop tufts of short erect threads upon the spots. These threads are each surmounted by a long slender spore, which in most cases is septate, or divided by transverse partitions, and is gradually attenuated upwards almost to a point. The British species (Ccrcospora Viola) has five or six rounded white spots on each leaf, upon which the mould is developed. The threads are very short, but the spores are very long (150-200 x 3h /.i), attenuated upwards, divided by numerous transverse partitions, threads and spores having a smoky tinge. It occurs also in Italy, Austria, and the United States. It is recommended to spray with dilute Bordeaux mixture. Sacc. Syll. iv. 2087 ; Sacc. /'. Ital. t. 651 ; Mass. PL Dis. 319. Another species (C. Viola- trieoloris), with longer olive threads, occurs .in Italy. A species (C. Viola-sylvatica), with shorter spores (45-70 //), is found on Viola sylvatica in the Netherlands. A British species {Ccrcospora Ii) has been found in Scotland on Viola palustris, with short spores (20-60//). In the United States Gercospora murina, with spores (25-35 x 4-5 /<), has occurred on Viola cucullata, and Ccrcospora, grcmuliformis, with variable spores on the same host. In Saxony C. lilacina has curved or sickle-shaped conidia (50-75 p long). DISEASES OF CARYOPHYLLACE/E. A synopsis of the diseases of the Carnation family has already been published, which did not attempt to include the parasites of uncultivated plants, and yet extended to a considerable length. It will be necessary here to give more explicit details of the several diseases, so that they may be recognised by the ordinary observer. Journ. B.H.S. xxvi. 1902, p. 649, PI. I. II. • DlANTHUS LEAF-Sl'OT. Phyllosticta Dicmihi (West.), PI: II. fig. 27. This leaf-spot occurs on the foliage of Dianthus barbatus in gardens. It is not a destructive fungus, except to the foliage, which it discolours and distorts to a considerable extent. The spots are whitish, ami sometimes two or three are run together into one irregular blotch. The receptacles are quite minute, but visible 30 FUNGOID PESTS OF CULTIVATED PLANTS. to the naked eye, scattered over the upper surface, but more clustered towards the centre of the spots, with the circumference almost bare. The sporules are elliptical and colourless, without any division, but usually with two or three small guttules (about 8 x 3 /u). At one time it was the custom to call these small sporules by the name of " spermatia," which led to the inference that they were fertilising, and not direct repro- ductive bodies. This name and supposed function were abandoned with the discovery that they were capable of germination under favourable circumstances. The present species has also been found in Belgium, where it was first discovered by Westendorp. If troublesome, spray with one of the copper solutions ; otherwise picking the diseased leaves may be sufficient to prevent recurrence. Sacc. Syll iii. 237 ; Journ. B.II.S. 1902, PI. I., f. 1. Phijllosticta tcuerrima is a Canadian species on leaves of Saponaria. Carnation Leap-spot. Ascochyta Dianthi (Alb. and Schw.), PI. II. fig. 28. The leaves of Pinks, Carnations, &c. are liable to be infested with another small parasite, which causes spots on the living leaves. The pale spots are somewhat rounded or elongated, without distinct margin, and are dotted with the minute receptacles, which are accumulated in patches, at first covered by the cuticle. The sporules are elongated, rather broader at one end than the other, but sometimes nearly equal, divided by a transverse septum in the centre into two cells ; each extremity is furnished with an obtuse nipple or apiculus (14-1G x 3^ /<). In this and similar cases, where the sporule or spore is divided into two or more cells, it may be taken for granted that each cell is capable of germination, and for all practical purposes acting as if each cell were an individual sporule. The little receptacles in which the sporules are produced are like little flattened round flasks, with a short neck, pierced at the apex, through which the matured sporules may escape. The base of these receptacles is attached to the delicate mycelium, upon which they are seated, and which pervades the spots. This species is also found in Germany and the Netherlands. Sacc. Syll. iii. 2203 ; Journ. B.H.S. 1902, p. 019, PL I., f. 2 ; Cooke Edbk. No. 1357. Lychnis Bkown Spot. m Sr/ilmiit I.i/cluiiilis (Desin.), PL II. fig. 29. This parasite occurs on irregular red-brown, or pallid-rufous spots, on the leaves of Lychnis dioica and other species. The spots have no definite margin, and arc sprinkled with the scattered receptacles, which are as minute as usual, and but just visible to the naked eye. The sporules are long and threadlike, often curved or flexuous, and divided by from five to seven transverse septa, (50 70 x 2', 8/ti). FUNGOID PESTS OF CULTIVATED PLANTS. 31 It has been recorded in France, where it was first discovered, and afterwards in Italy and Great Britain. Sacc. Syll. iii. 2804 ; x. 631N. Another species, with round pale spots, margined by a narrow bright brown ring {Septoria noctiflora), occurs on Silene noctiflora in America. One species without any definite spots (Septoria dianthicola) attacks the leaves of Sweet Williams and Pinks in Italy and Portugal. Another affects the leaves of Saponaria (Septoria Saponaria) in France, Italy, and Germany, in which the spots are pallid and rounded or irregular, the sporules being more robust than usual. The leaf-spot most prevalent in Europe, S. Africa, and Australia (Septoria Dianthi) is not recorded for Britain. (See Journal K.H.S. 1902, PI. I., f. 3.) Large Dianthus Spot. Septoria Sinarum (Speg.), PI. II. fig. 81. This leaf-spot seems hitherto to have been confined to the leaves of Dianthus sinensis, which are blotched with large and somewhat rounded whitish spots, often occupying the greater part of the leaf, and without any definite margin. The receptacles are scattered over the upper surface of the spots. The sporules are of the threadlike type, but very short for fungi of this kind (20-25 x 2-2i^). The species was first found in Italy, but has since migrated to Britain. Sacc. Syll. iii. 2802. "We may just mention Septoria, dianthophila which affects the stems of Dianthus Caryophyllus in Brazil. Two species are recorded as selecting specially the calyces of Dianthus for their host. One of these is named Septoria Carthu- sianorum, and occurs in Belgium ; whilst the other is called Septoria calycina, and is given as Belgian also ; but except in the names we fail to detect any difference between them, and suspect that it is the same parasite described independently by two different persons. Carnation Anthracnose. Gloeosporium Dianthi (Cooke). During the spring of 1902 Carnations in several localities were attacked by this pest before it could be found in fructification and described, as it would appear to be an entirely new pest. The leaves are at first spotted with small purple roundish spots. These gradually enlarge and become confluent and indeterminate, and at length brownish in the centre. Meanwhile the leaves become sickly, and commence to die off at the tips. The pustules are not to be distinguished by the naked eye, and scarcely by the aid of a lens. Cells beneath the cuticle supply the place of definite receptacles, and in them a large number of elliptical hyaline sporules (10-12 x 5 /«) are produced, which 3l> FUNGOID PESTS OF CULTIVATED PLANTS. escape through the fissured cuticle. At length the cuticle about the orifice turns pallid, and appears as a pale dot on the purple spot-. No remedies have been tried, but it would be advisable to apply diluted Bordeaux mixture, so as to destroy the extruded sporules, and to pick off as many of the diseased leaves as possible. Observed since the plates were in press, and hence too late for illus- tration here. SEPTATE-CABNATION A.NTHRACNOSE. Marsonia Delastrei (De Lacr.), PI. II. fig. 82. We venture to include here references and descriptions of another of those destructive forms of disease which is called in America "An- thracnose," although there was no record of a British species until the immediately preceding species was discovered as this description was going to press. They form spots on leaves and stems, but there are no definite receptacles, only cells or cavities in the substance, which are covered by the cuticle The sporules are formed in these cavities, and are liberated by the rupture of the cuticle. The spots on the leaves of Lychnis are tawny and without definite margin. The sunken cells are scattered over these spots. The sporules are narrowly club-shaped, rounded at the apex, and attenuated towards the base. They are colourless, and at first without division, but at length are divided by a septum in the centre into two cells (20-25 x 6-7/<), and are at first attached to long slender threads. Because of the divided spores it is called Marsonia. If the spores were undivided it would be Glaosporium. Evidently this is only a mature form of another described parasite called Gl&osporium Lychnidis, with which it agrees in every respect except in the septation of the sporules, both occurring upon the same host. The distribution of this species is France, Belgium, the Netherlands, Germany, Austria, Italy, and Siberia. Diseased parts should be collected and burnt. Sacc. Syll. iii. 3700; iv. 4035; Journ. R.H.S. 1902, p. 650, PI. I., i. 1. A similar parasite {Gylindrosporium Saponaria) is found on the leaves of Soapwort in France. The sporules are straight and cylindrical (10-40 x ?>},,.). .loins. K.II.S. 1902, p. 050, PI. II., f. 17. Soapwort Smut. Sorosporiwn Saponaria (Bud.), PI. II. fig. HI. This smut occurs chiefly on the Continent upon the inflorescence of the Soapwort, on which it has been known for half a century. Only recently has it made its appearance in gardens in this country on Dianthus tlcl(<>/tlcs. It attacks ami destroys the reproductive organs of the flowers, converting them into glomerules of spores. The spore masses, or glomerules (40 100 /< diam.), are rounded and composed oi .1 great number of loosely connected cells, or teleutospores, FUNGOID PESTS OF CULTIVATED PLANTS. 38 -which are yellowish-brown and angular from mutual pressure. The outer surface is rough with little tubercles and ridges (12-18 x 10-14 jx). The spores have been induced to germinate artificially, but not to proceed to the formation of secondary spores. In the majority of species of the "smuts " the spores and glomerulus are very dark brown, or almost black, and hence the name ; but in a few species — and this amongst the number — the colour is pale. Undoubtedly the smuts may be disseminated by means of the spores, but at the same time there is strong evidence in support of a perennial mycelium in perennial plants. The present species is known in France, Germany, Austria, Italy, and Algeria, as well as Britain. Difficult to combat, but seldom occurs in this country. Better to burn infected plants. Sacc. Syll. vti. 1872 ; Ploicr. Brit. Ured. p. 296 ; Mass. B. F. p. 202. figs. 59, 59a ; Journ. B.H.S. 1902, p. 650, PL II., f. 9. Anther Smut. Ustihujo violacea (Pers.), PI. II. fig. 33. This smut habitually attacks the flowers of many species of Caryo- phyllaccce, chiefly appropriating the anthers, and converting them into a mass of blackish powdery spores, which are diffused and scattered over the petals. In older books it is known as Ustilago anthcrarum from its habit' of growth. The spores are subglobose and lilac under the microscope, covered with a network of ridges (6-9 f< diam.), the meshes being about h p apart. On germination a fusiform promycelium is formed, which is commonly three-septate, each joint giving origin to a secondary spore, or sporidiole, of an ovate form. This species is known also in France, Belgium, Germany, Switzerland, Austria, Bohemia, Transylvania, Italy, and North America. Naturally there can be no remedy, as the presence of the parasite is unknown until it makes its appearance in the flowers, and then it is too late. All that can be done is to destroy all infected plants, so as to pre- vent the spread of the disease. Sacc. Syll. vii. 1781 ; Cooke M. F., figs. 102-104 ; Plowr. Brit. Ured. p. 280; Mass. B. F. p. 179; Cooke Hdbk. No. 1534; Journ. B.TI.S. 1902, p. 651, PI. II., f. 11 ; Tubeuf, Dis. p. 297. Sweet William Brand. Puccinia Dianthi (DC), PI. II. fig. 35. One of the most common and best known pests of Sweet Williams and other allied plants, attacking the living foliage and rendering them most unsightly. There are usually large pale spots upon the leaves, which are somewhat rounded, or one or two other spots are joined to make them irregular, or to occupy nearly the whole of the surface of the leaf. The pustules are rounded and cushion-like, either disposed in circles on the spots, or running together and forming an irregular crust, which D 34 FUNGOID PESTS OF CULTIVATED PLANTS. is at first pale brown, then dark brown, covered with the pale cuticle, which splits irregularly, leaving the ragged margins like a frill round the pustules. The teleutospores are fusoid or clavate, rounded at the apex, or conical, with the epispore thickened, divided at the middle into two cells, the lower one attenuated downwards into the hyaline pedicel (30-50 x 10-20 /.i), pale in colour, and ochrey-brown. No cluster-cups, or uredo, known to be associated with this species, which is reported over the greater part of Europe, Asiatic Siberia, and North America. In some books it is called Puce hi la Armaria, and in others Puce in ia Lychnidearuvi. There are authors to whom names are pretty playthings, to be tossed about as they please. Doubtless infection is transmitted of this disease through imported seeds. Sacc. Syll. vii. 23G1 ; Mass. PL Dis. 253 ; Cooke Hdbk. No. 1503 ; Cooke, 31. F. p. 210 ; Ploicr. Brit. Ured. p. 210 ; Gard. Chron. Jan. 12, 1884, p. 57 ; Jan. 2G, 1884, p. 120 ; Journ, E.H.S. p. 652, PI. I., f. 5. Campion Brand. Puce i iiia Silencs (Schrot.), PI. II. fig. 36. We are not prepared to affirm to what extent this pest has worked in gardens, but it is common on wild plants, and we fear sometimes on cultivated ones also. It occurs on the living leaves of almost any species of Silene and Melandryum throughout Europe. The first stage, or cluster-cup (JEcidiwm Behenis), appears in the spring on the Bladder Campion, in small rounded clusters of the usual appear- ance, with white fringed margins and orange spores. The recidiospores are angular and granulated (17-26 x 14 20 /<). The pustules of the uredo form come later, and are rather small, either scattered, or at times confluent, and the uredospores are elliptical or ovoid, externally rough (19-26 x 17-22 /j), pale brown. The teleutospores are contained in darker pustules, of a similar form and scattered, but not collected upon bleached spots. They are elliptical, or ovate, quite different in general outline from those of the Sweet William brand, rounded at both ends, and divided in the middle into two equal cells (25-40 x 16-25 /a), externally smooth, and of a chestnut- brown colour, with a short and uncoloured pedicel. The area of distribution includes France, Belgium, Germany, Switzer- land, Italy, and Siberia, as well as Britain. Dilute Bordeaux mixture has been recommended as having proved effective. Sacc. Syll. vii. 2154; Jowrn. E.H.S. 1902, p. 652, PI. 2, f. 15; Cooke M. /'. p. 211; Phwr. Brit. I'm/. 147. Puccinia fastidiosa on ]>if the undo are rounded, rather small and of a reddish or chestnut-brown. The uredospores, which are soon set free hy the rapture of the cuticli . lobose and rough (22-21 fi diam.), of a pale chestnut-brown colour. Th« i or brand spore-, air produced in dark brown • shortlj elliptical, almost globose (19-22 x 17-20 fi), .lark brown, clad with obtuse Btoutish warts, growing at first on a slender hyaline pedicel, which soon falls away. If applied early, fungicides will prevent the spread of this disease, but the teleutospores are capable of acting as resting spores, carrying the !i the w inter. . S\ I. vii. 1966; OrevUle Eng. Flor. v. p. 383; Plowr. Brit. Another species [Uromyces Lupini) is found on the same Lupins in . . and the spots are traversed by the mycelium. It is generally thought that in these leaf-spot diseases spraying with Bordeaux mixture may be of service. At any rate the spread of the disease may be checked by persistently destroying diseased leaves. Sacc. Syll hi. 2782 ; Grcvillca, xiv. 101. B Fi«. 6. — Endophyllum Sempervivi, attacking Sempervivum monticolum. A, Entire plant ; B, C, Leaves. (Gardeners' Chronicle.) Although the above is the only parasite upon Oenothera which has yet appeared in this country, there are other species known, especially in North America, such as JEcidium Peckii, and JEcidiiim Oenothera, Puc- cinia CEnotherce, and Pucciniastrum (Enothcrce, Uromyces (Enotherce and Uromyces plumbarius, in addition to a rot-mould, or Peronospora. As these have not crossed the Atlantic, a favourite cottage flower flourishes with us comparatively unharmed. 18 ITXGOID PESTS OF CULTIVATED PLANTS. Fuchsia Diseases. Although the Fuchsia is largely grown in this country, its enemies are very few, and, so far as we are aware, none of a fungus origin have as yet been found, although a leaf-spot is known in France. Houseleek Rust. Endophyllum Sempervivi (A. & S.). This peculiar parasite is somewhat intermediate in its character between a uredo and a cluster-cup. The envelope which encloses the spores is immersed in the Bubstance of the succulent leaves, and bursts irregularly to discharge the spores. The teleutospores, as they are termed, are for the greater part rounded orobovate (25 86 x 20-32 fi), with the surface warted and of a brownish- yellow colour. They germinate after the manner of those of Puccinia. The sp eies is known over the greater part of Northern Europe. D * *-f#0j y 5 X 20 XJ20- 1 ra. 7. Endophyllum Sempervivi, D, Section through affected leaf, magn.; E Seotion through pustule, magn. ; F, Spores, magn. Sacc. Syll. vii. 2676; Oard. Chron. May 22, 1880, p. GGO, with fig.; I /'.-. M.F. 200; Cooke Hdbk. No. 1686; Ptowr. Brit. Ured. 229. II"- i \ si ckle Leaf-spot. Phyllo8ticta I. (West), PL 111. fig. 56. The Hone) uokle maj claim to be a garden flower, and is certainly a favourite in cottage garden . The leaf-spots are rounded and pallid, with a brown margin, and the perithecia are quite small, appearing like very minute dots upon tin The sporulea are rather larg< for the genua to which they belong, and are narrowly elliptical, with two nuclei (10 llx2i~8.\ ft), and colon lit FUNGOID PESTS OF CULTIVATED PLANTS. 49 The spot is known also in France, Belgium, Germany, Austria, Italy, Portugal, and the United States of North America. Sacc. Syll. iii. 90 ; Cooke Hdbk. No. 1353. A similar leaf-spot with large brownish spots, and very minute sporules, P. nitidula, is found in Algeria, whilst another species with greyish spots, P. Caprifolii, occurs in Italy, France, and Siberia. Species with two-celled sporules are known, one in France and one in Italy, as well as another in Belgium. Two species with thread-like sporules are also known, the one in Switzerland and the other in Portugal. Honeysuckle Cluster-cups. JEcidium Periclymcni (Schum.). Although the cluster-cups are usually found upon uncultivated plants, it is not an uncommon British parasite, and is one of those species to which no Uredo or Puccinia has been affiliated. The spots on the leaves are roundish, or oblong, and yellowish, whilst the cups are clustered together on the spots. The cups are somewhat cylindrical, with a fringed white margin. The tecidiospores are roundish, sometimes angular by compression (16-28 fi diam.), delicately warted, and orange in colour. The species is recorded also in France, Belgium, Germany, Switzer- land, Italy, and Siberia. Sacc. Syll. vii. 2809 ; Cooke M.F. 196 ; Ploicr. Brit. Ured. 264. Another species {JE. lonicerinum) is reported to be found upon the living leaves of a species of Honeysuckle in Asiatic Siberia. Honeysuckle Black Blotch. Lasiobotrys Lonicerce (Kunze), PI. III. fig. 57. This is a peculiar parasite which has been known in this country for many years on living Honeysuckle leaves, although not likely to give much trouble in gardens. The leaves are spotted with several roundish black shining blotches (2-5 m. diam.). An external stromatic cup, which ruptures irregularly, encloses a number of black receptacles or perithecia (50 /j. diam.) densely clustered together. Each of these perithecia contains a number- of club-shaped asci, or membranous sacs, which include the sporidia, eight of which are enclosed in each ascus. These sporidia are shortly fusiform and colour- less (8-10 x 4-5 /u), which are set free by the irregular splitting of the perithecia. The pustules are sometimes quite round, black, shining, and convex, so that they appear to be superficial, like little spots of pitch on the leaves. It is recorded for France, Belgium, Germany, Italy, Algeria, and Siberia. It is so rare on Honeysuckle in gardens that the effect of fungicides has not been determined, but they are scarcely to be relied on for so deeply seated an endophyte. Sacc. Syll, i. 121 ; Cooke Hdbk. 1909. s 50 FUNGOID PESTS OF CULTIVATED PLANTS. Although the powdery mildew (Microsph'aria Ehrenbergii) has been found on Honeysuckle leaves on the Continent, we have no record of it in Britain. PESTS OF COMPOSITE PLANTS. It seems rather remarkable that so large an order of plants as the . containing many garden flowers, should be so conspicuously free from the atttacks of fungoid parasites. Who shall explain wherefore Puccinia Helianthi (Schum.), which is so universal in North America on Sunflower and Jerusalem Artichoke, has never made its appearance in this country, although it has been reported in Europe ? Why are Dahlias so impervious to attack, and a host of smaller annuals, Asters, Coreopsis, Marguerites, and the plebeian Marigold, go almost free ? Even the cultivated Cineraria, which is popular enough in all conscience, has never received a check in this country, although it has been threatened abroad. Chrysanthemum Leaf-spot. It will be well to be guarded against the occurrence of leaf-spot on Chrysanthemums, as some three or four exotic species are already known. The purple spot (Pliyllosticta Chrysanthemi), with small simple sporules (4-5 x 2^-3 /(), has up to the present been found only in Canada. The ringed brown spot (Septoria Chrysanthemi), with long thread- like sporules (55-65 /u long), has apparently been confined to Italy. This i- the most essential to be watched of all, since it is European. The black spot (Cylindrosporium Chrysanthemi) is very destructive in Canada, and has large, sooty, indefinite spots, with fusoid conidia (50-100 x B-4 1 , //). When the leaves are attacked they soon turn yellow and shrivel, and the flower buds do not expand. Mass. PI. Dis. 292. Chbtsanthemum Oidium. Oidium Chrysanthemi (Rabh.), PI. III. fig. 58. This effused white mould is found on the leaves of Chrysanthemum, hut fortunately it has not hitherto been sufficiently common to cause alarm. The thin white mealy patches are without definite form, and consist of a creeping mycelium from which the fertile threads arise. These are at first just like simple threads, with cross divisions, separating them into joints : Imt at Length the upper joint enlarges and becomes elliptical, and when i' foils away as a conidium or sporule, capable of germination, ic be followed li\ the next joint and the next, and so on in succession until ji largt number of conidia are produced and thrown off, as in other species of Oct nun. The conidia are rather large (10-50 x 20-25 /i) as compared with other Bpi i It may he a BUmed that such remedies as are successful with Oidium on the sine would be applicable here, and of these the application of sulphur i- most to 1» commended. The above-named mould appeared in this country for the first time in 1884, and I known also in France and Germany. . Syll. iv. 199 ; Qard. Chron. Nov. 29, 1881, fig. 118; lb. 1901, p. 851. FUNGOID PESTS OF CULTIVATED PLANTS. 51 Chrysanthemum Bust. Ureclo Chrysantliemi (Arth.), PL III. fig. 59. When this rust was first observed on the leaves of Chrysanthemum in 1897 it was believed that it would be discovered to be the Uredo form of Puccinia Hicracii, and hence was called Uredo Hieracii; but it has since been shown that it must be regarded as a distinct species, for which no teleutospores have yet been found. The pustules of the Uredo occur on the under side of the leaves, which soon split irregularly and discharge the powdery snuff-coloured spores, and these readily disperse themselves over the surface of the leaf. The uredospores are somewhat elliptical, with a rough surface (17-32 x 16-86 f<), and irregular in size. This pest at one time threatened to spread over France and this country, and produce havoc amongst Chrysanthemums, but it has since been brought under control. Spraying with potassium sulphide solution is recommended, especially upon apparently clean leaves, while rusted leaves should be carefully removed. Paraffin has also been recommended in dilution. It should be remembered that uncultivated composite plants are, of all others, most susceptible to the attacks of rust and brand, and it is in that direction that danger lies. Gard. Chron. Oct. 8, 1898, with figs. ; Mass. PL Dis. 241 ; Joum. B.H.S. xxvi. 1902, p. 915 ; xxviii. 1904, p. 634 ; xxix. p. 769. Great trouble in the United States in growing Asters on account of fungoid disease. {Joum. B.H.S. xxvi. 1901, p. 531.) Corn Flower Rust. Puccinia Centaurece (DC), PL III. fig. 60. During the past year or two Corn flowers in cultivation have been seriously attacked by this rust, which has long been known on unculti- vated species of Centaur ca. We have nothing to do with the JEcidium here until it is proved to be distinctly related to the rust on Cyanea. The Uredo appears on the stem and leaves in elliptical pustules, which are longer on the stems, soon fissured, and exposing the snuff-coloured uredospores which are almost globose (22 jj. diam.), and we could detect no roughness on the surface. The colour was pale brown under the microscope, and certainly not, as some have stated, chestnut-brown. It is the custom in these latter days to lump together a number of the species of rust found on composite plants under the name of Puccinia Hieracii, and this among the number. For the present we prefer to call it Puccinia Centaurece. We can only suggest the spraying of healthy plants, or those but slightly affected, with the potassium sulphide solution and burning badly diseased plants out of the way. Sacc. Syll. vii. 2210 ; Ploiur. Brit. Ured. 186 ; Cooke M.F. 63, 207 ; Joum. B.H.S. xxvi. 1901, p. cxxv. 52 FUNGOID PESTS OF CULTIVATED PLANTS. Senecio Rust. Coleosporium Senccionis (Pers.), PI. III. fig. 61. A common bright orange rust is to be found every season on the under side of the leaves of the Common Groundsel and other indigenous species of Senecio. Occasionally the same species makes its appearance in gardens on the leaves of cultivated species of the same genus, such as Senecio pulcher and S. sarracenicus. Theorists tell us that the aecidiospores of this pest are produced on the leaves and twigs of certain conifers, which, not being garden flowers, may here be excluded. Even the believers are a little sceptical, for Plowright says : " I have had so many failures in infecting Senecio vulgaris with the a^cidiospores from Fir trees that I think there must be more than one species." The pustules of the Urcdo are reddish-yellow, soon becoming paler and powdery. Uredospores shortly catenulate, or growing in chains, then separating, elliptical, ovoid (20-40 x 14-26 n), warted, orange. After- wards teleutospores are said to be produced in other darker-coloured pustules. Teleutospores cylindrical (110 /j. long), for the most part divided transversely into four cells of an orange-red colour. We can suggest no remedy, except prevention, by keeping all wild species of Ragwort at a distance and destroying infected plants, as the garden forms are not apparently so susceptible to the disease. Universally diffused through Europe. Sacc. Syll. vii. 2633 ; Mass. PL Dis. 261 ; Cooke M.F. 97, 218, figs. 145, 146 ; Tubeuf, Dis. 374, fig. ; Plowr. Brit. Ured. 240. Recently JEcidium Cineraria has been detected in Austria on leaves of Cineraria. Ptarmica Dot. Schizothyrium Ptarmica (Desm.). I 'hints of Achillea Ptarmica are to be met with in old-fashioned gardens, and the green leaves are liable to the attack of a special fungus. The leaves and stems are at first ' dotted over with the small black points of Leptothyrium Ptarmica. These minute black receptacles con- □ a number of oblong sporules, with an apparent central division (10 x 6-7 fi). This is regarded as an early and imperfect condition of a more highly developed parasite, which resembles it in size and appearance, and often .'/rows in company with it. This latter, ox ScMzothyriv/m, came over from France with imported plants many years ago. To the naked eye they look like fly spots, causing no discoloration of the foliage. The receptacles are flattened and open on the upper surface, enclosing minute ovoid sporidia (10 /.i long), enclosed in asci, closely packed Bide by side in the interior. It has evidently a jm rennial mycelium, since the dots or receptacles will continue to appear on the same plant year after year for many years. The plants are stunted, but not much disfigured by the parasite. The di is known in France, Belgium, Germany, Finland, and Siberia. Sacc. Syll. ii. 0559, hi. 3379. PESTS~FLOWER GARDEN. FUNGOID PESTS OF CULTIVATED PLANTS. 53 Lobelia Dot. Phoma dcvastatrix (B. and Br.), PI. III. fig. 62. For the first time, in 1856, the clumps of Lobelia in gardens were attacked by a minute parasite, which was so destructive that it secured for itself the specific name of " the destroyer." It is seldom that the fungi of the group to which this pest belongs make any attack upon living plants, being largely restricted to dead stems and dead leaves and twigs. The dots or receptacles, which, with their mycelium, represent the entire fungus in this instance, are scarcely visible to the naked eye. They consist of a minute globose body, like a pin-point, or a small black dot, containing a number of colourless sporules, which are long and narrow (8-10 /j), rounded at the end and furnished with two or three nuclei. Fortunately in this case it took the form of an epidemic, which gradually passed away, and for many years not an example has been seen. For a deep-seated disease like this there is no effectual remedy and no protection, except to root up bodily all the plants which are, or are likely to become, infected and burn them. This disease appeared afterwards also in the United States. Sacc. Syll. iii. 791 ; Cooke Hclbk. No. 1221. About a dozen other parasites on Lobelia are recorded, most of them in North America. PRIMKOSE PARASITES. The Primrose family seems to be rather susceptible of fungoid diseases, although perhaps their virulence is not upon an equality with their number. The most dangerous, the rot-mould, has never established itself as a pest, and the commonest are the leaf-spots. Most species of Primula appear, however, to be liable to attacks from the rusts and smuts. Primula Leaf-spot. Phyllosticta primulcecola (Desm.), PI. IV. fig. 64. This endophyte is not a very common disease of the leaves of Primula vera and Primula elatior in France and Belgium, whence it probably extended to Britain. Discolorations sometimes seen on leaves of culti- vated Primulas, which do not perfect themselves, may belong to this species. The spots are white, circular, and rather large on both surfaces, with a tawny margin. Sometimes the spots are naked, but at other times are dotted with the minute blackish receptacles, which are then very numerous, and, especially towards the centre, just visible to the naked eye. The sporules developed within the receptacles are exceedingly minute, and are extruded in considerable numbers when mature (1-5 x 2-3 /i). Sacc. Syll. iii. 308 ; Cooke Hclbk. No. 1319 ; Grevillea, xiv. 71, No. 133. Scotch Leaf-spot. Ascochyta Primula (Trail), PI. IV. fig. 65. This second leaf-spot has occurred in Scotland on Primula vulgaris, and is exactly similar in external appearance to the foregoing. The 54 FUNGOID PESTS OF CULTIVATED PLANTS. sporules, however, are larger (5-6 x 2h /<) and divided by a transverse septum into two cells. ■c. Syll. x. 5969 ; Grcvillea, xv. 1887, p. 108. Wild Primrose Leaf- spot. Septoria Primula (Buck), PI. IV. fig. 66. We have included also this leaf-spot, which was found on the leaves of uncultivated Primroses near Bristol, and, apparently, has not been recognised elsewhere. The spots are conspicuous chiefly on the upper surfaces of the leaves, and are somewhat rounded and pallid, with a brown border. The peri- thecia are dot-like, and are scattered over the spots, which are scarcely to be distinguished from the other two forms of leaf-spot. The sporules are very different, for in this instance they are long and threadlike (45-50 \i long) and apparently nucleate. It has never been shown that there is any connection between these three genera of leaf -spot fungi, and it is scarcely probable, since any genetic connection would probably be with fungi of a higher order, and, presumably, of the Sphariacece. Grevillea, xiv. 1885, p. 40 ; Sacc. Syll. x. 6389. Primrose Smut. Urocystis primuUcola (Magn.), PI. IV. fig. 75. In some of its features this smut bears slight resemblance to the Violet smut, but it differs in that it attacks the fruit, so that all the seed capsules are filled with smut instead of seeds, and unless eradicated will continue to appear year after year. Its first appearance in this country was recorded in the autumn of 1884 upon Primula farinosa, although it aid to have been seen as far back as 1867. The glomerules of spores are roundish or irregular, and are composed of from seven to ten teleutospores, which are normally globose, but become angular by compression, of a dark brown colour, and smooth (9-15 /i). The outer circle of sterile and pale-coloured spores is nearly of the Bame size and shape. ' ri i munition takes place after a similar manner to that of the Violet smut. A short thick process or promycelimn is thrust out, and this bears another generation of -mailer and secondary spores at its extremity, and these again can produce their like. These secondary spores are engaged in the di emulation of the species. This is a deep leated endophyte, not to be dislodged when once it tab |" • on of a plant. Ii has been found in Silesia, Saxony, and Italy. Sacc. SylL-m. L899; Qard. Chron. Aug. 30, 1884, fig. 52 ; Plowr. . 289. PrIMBOSB Clil si i:i; ( UPS. . Ecidium Primula, DO. These cluster-cups, on the leaves of Primula of various species, might have been included with the rust, only that the habit is so different as to FUNGOID PESTS OF CULTIVATED PLANTS. 55 appear like a different disease, and the ordinary observer might well be puzzled. There is no doubt of its being a prelude or an early stage of the rust ; but it may appear without the rust, and the rust may be seen quite independently of the cluster-cups. The cups are usually clustered together on the under surface upon discoloured spots, which are also distinctly indicated on the upper sur- face. The cups are rather urn-shaped, partly immersed, with a white fringed margin. The secidiospores, at first globose, are soon angular, with a roughened surface and yellow (17-23 x 12-18 /x). Of course, as usual, produced in chains within the cups. The area of distribution is the same as that of the rust. Hitherto cluster-cups have not generally been regarded as trouble- some garden pests, so that picking off and burning diseased leaves has been considered sufficient to prevent spreading. Sacc. Syll. vii. 2170 ; Cooke M.F. p. 199 ; Cooke Hdbk. No. 1631 ; Ploicr. Brit. Ured. p. 159. Primrose Bust. Pucciuia Primula (DC), PL IV. fig. 70. This is one of the species of rust which passes its three stages of cluster-cups, Credo, and Pucciuia upon the leaves of the same plant. Doubtless it is more often met with on wild than on cultivated plants, but its existence is not therefore to be ignored. The pustules of the uredospores are aggregated together in some- what orbicular spots, soon splitting the cuticle and setting free the powdery uredospores, which are rounded or ovoid (19-22 ^) and minutely rough on the surface, of a pale brown colour. The pustules are found on the under surface, as well as those of the teleutospores, which latter are scattered or sometimes gregarious, and darker in colour. The teleuto- spores are somewhat elliptical, with a central division into two cells, the upper of which is rounded at the apex and the lower a little narrowed into the very short stem (22-30 x 15-18 /u), externally smooth, brown, with the outer coat thickened at the apex. Its distribution is recorded for France, Belgium, Switzerland, Ger- many, and Finland, as well as Britain. All the rusts are difficult of treatment, and seldom can be checked to any considerable extent by the use of fungicides. Efforts should be directed rather to check dispersion and extension. Sacc. Syll. vii. 2170; Cooke 31. F. 204; Hdbk. No. 1471; Ploior. Brit. Ured. 159. Primrose Simple Brand. Uromyces Primula (DC), PI. IV. fig. 69. Found on the leaves of Primula intcgrifolia and Auricula, and the theorists have, singularly enough, united this species, as well as Pucciuia Primula, with the Primrose cluster-cups {JEcidium Primula) as the secidiospore form. Hence the one JEcidium must be held to be respon- sible for two species of teleutospores. La the present endophyte the teleutospores are elliptical or ovoid (20-35 x 10-20 n) and warted, with a hyaline papilla at the apex and a 56 FUNGOID PESTS OF CULTIVATED PLANTS. short deciduous pedicel at the hase. The teleutospores differ from those of Puccmia in being one-celled. The colour is also brown. The uredospores are supposed to be unknown, although the pustules of the teleutospores are said to be sometimes intermixed with the cluster- cups. Never having seen them in this connection, we cannot vouch for the authenticity of the assertion. This endophyte has been recorded, not only in Britain, but also in France. Germany, Austria. Italy, and Asiatic Siberia. Sacc. Syll. vii. 2007 ; Cooke M.F. 227. Pkimrose White Mould. Ovularia i?iterstitialis (Cooke), PI. VI. fig. 67. Under the name of Peronospora interstitialis this mould was first made known by Berkeley in 1H75 from specimens obtained from Scotland, but at the time he seems to have had a suspicion that it was not a true Perono&pora, since confirmed. It was afterwards quoted as Bamularia interstitialis ; but that even is scarcely tenable, and we substitute the above. It occurs in yellowish patches on the under side of the leaves, in the spaces between the veins, rarely occupying any extended surface. The i breads are short and fiexuous, apparently unbranched, with a few pro- jecting spicules in the upper portion to support the conidia, which are elliptical and either apical or lateral (which Berkeley calls " oblique "), but there is no evidence of septum (15-17i x G-7/x). We believe it to be the same species as Ovularia primulana (Karst) found in Finland, also on the leaves of Primula vera (Sacc. Syll. iv. 787). This is the kind of parasite which is likely to be amenable to the influence of fungicides, and has none of the pertinacity, or the resting spores, of the rot-moulds. Sacc. Syll. vii. 867 ; Berk. Ann. Nat. Hist. 1875, No. 1455 ; Gard. Chron. May 1, 188G, fig. 124; Grevillca, iii. 183. Pkimrose White Mould. I ; i i miliaria Primula (Thiini.), PI. IV. fig. G8. Tin | k 1 1 in this disease are circular or somewhat angular, and of a pale ochraceous colour, without a definite margin, upon which the mould is bed in tufts on either surface. The threads are rather long (50 -GO x 5/i), without septa or divisions, but very rarely at all branched. The conidia are cylindricallj fusiform (20-80 x 3-6/;) and sometimes uniseptate, or with one nan ver e division, and uncoloured. Our own measurements are somewhal differenl (26 / ;">/<)• Would be iibmiasive bo spraying with dilute Bordeaux mixture. Tbi mould has been recorded in Italy, Austria, and Siberia, as well as in Britain. Sacc. Syll. iv. lOK); Sacc. /•'. Ttal. t. 985. A black mould (< ora Primula) seated on whitish-grey spots of the Leaves of Primula elatior has occurred in France. The tufted threads FUNGOID PESTS OF CULTIVATED PLANTS. 57 are short and olive, whilst the conidia are long and narrow (60-100 x 4 ft), attenuated upwards almost to a point, and divided transversely by eight or nine septa. Primrose Rot-mould. Pcronospora Candida (Fckl.), PI. IV. fig. 70*. Although of rare occurrence in this country, the above rot- mould has made its appearance on wild plants, without visiting and inflicting damage on cultivated species, except on rare occasions. White mouldy spots appear on the under side of living leaves which are conspicuous by their snowy whiteness, although not very dense. Slender erect threads arise from the creeping innate mycelium which are many times branched in the upper portion in a forked manner. The final branches are short and spreading, acute at the tips, and bearing singly the elliptical conidia, which are comparatively small (22-26 x 16-30 ft) and hyaline. Within the substance of the petioles and stem the mycelium produces the usual resting spores, which have a yellowish and afterwards a bright brown and rather thick integument (30 x 33 ft). These bodies provide for the rejuvenescence of the parasite in the spring by remaining at rest through the winter. The production and development of these resting spores have already been described in the introduction (ante, p. 2). The distribution of this parasite is narrow, only Germany and Belgium having been recorded in addition to Great Britain. It has never been sufficiently prevalent or destructive to have been experimented on with fungicides. Sacc. Syll. vii. 860 ; Card. Chron. May 1, 1886, with fig. ; Cooke M.F. 237 ; Cooke Hdbk. No. 1786. Cyclamen Leaf-spot. Two kinds of leaf-spot have been described on the leaves of Cyclamen, but neither of them has as yet been decidedly recognised in this country. The French leaf-spot, Phyllosticta Cyclaminis, is manifested by some- what circular brown spots over which the minute perithecia are scattered, and the sporules are small, narrowly elliptical (6-8 x 2 ft), rounded at the ends, and colourless (Bull. Soc. Myc. de France, 1893, t. xiv., f. 4). The other species, which we may call the " Concentric Cyclamen Spot," forms rather large and irregular smoky spots, with a rufous margin, the surface being concentrically lined (Septoria Cyclaminis). It was first described in the " Flora of Algeria." The sporules are long and threadlike (25-30 x 1 ft), divided by three transverse septa. This species has occurred in Italy as well as Algeria. So far as we are aware, these are the only fungus parasites which have been described as troubling the Cyclamen. Auricula Brown Mould. Heterosporium Auricula (Cooke), PI. IV. fig. 71. About the year 1888 this parasite was first brought to our notice, flourishing upon living leaves of Auricula, and then threatening to 58 FUNGOID PESTS OF CULTIVATED PLANTS. become troublesome ; however it scarcely seems to have appeared since, or during the pa Pia. '.». Dbomyobb Ebtthbonxi. L. Portion of a loaf showing clusters of the fungus. N;it. Bizo. '-'. A single group of the fungus fruit known popularly as • oluster-oup LOO. 8. Credo, or Bummer-spores : x 400. Teleuto- or wintei Bpon : 100. Suriu, J'»i;\m». Uromycea Scillarum (Grev.), PI. \'. fig. H6. This parasite is vcrj common on the loaves of the Wild Hyacinth, and probably has thence found its way into gardens, where it attacks the Leaves of Musca/ri botryoides and other species. The attacked leaves are blotched with paler spots, upon which the IP. 103 S>3 0»> I IOM- $.' ft'/* Q> \o5 ^ 110 a 1. 109 )0Z .»# .07 // ¥ 7*1 -C C u% U5 )' PESTS-GARDEN VEGETABLES. FINGOID PESTS OF CULTIVATED PLANTS. 69 pustules soon appear, at first covered by the cuticle. The paleness is caused by the internal mycelium which pervades the tissues. The pustules are small and numerous, generally arranged upon the spots in concentric rings, or parts of rings, with a tendency to coalesce. The spores are soon exposed by rupture of the cuticle, when they are powdery and of a chestnut-brown colour. The uredospores are at present unknown. The teleutospores are subglobose, or rather pear-shaped (19-30 x 14-24 p), and sometimes irregular by compression, quite smooth, and of a pale brown. The epispore, or spore coating, is of equal thickness throughout, and not thickened at the apex, as in many other species. There is a short hyaline stem, which soon disappears. Its area of distribution, outside this country, includes France, Germany, Austria, Hungary, C4reece, Italy, Egypt, and South Africa. It is possible that spraying with * one of the fungicides may be of a little service, but the perfection and dispersion of the spores should be prevented by picking and destroying infected leaves. Sacc. Syll. vii. 2014; Cooke 2I.F. 213; Cooke Hdbk. No. 1548; Plowr. Brit. Ured. 141 ; Grcvillea, vii. 138. Black Smut. Sclerotinia bulborum (Wakk.), PL IX. fig. 135. A pest under the name of "black smut" has appeared around Haarlem, where it has been very destructive to Hyacinth culture. It is not a " smut " according to our acceptation of the term, but a Sclerotium. It makes its appearance after flowering, causing the leaves to turn yellow and fall off. No external mycelium is to be observed, except at the base of the leaves. The bulb is completely permeated with mycelium, and black irregular nodules appear on the surface, mixed with some that are softer and paler coloured. These are the " sclerotia," or nodules of compact mycelium. These nodules are like resting scores, and must pass through a period of quiescence, so that they will not germinate until the following spring. If the bulbs are potted, and watered copiously, at the period when their activity should commence the sclerotia will germinate and produce the little Peziza cups, resembling those produced from the sclerotium of the Potato. To this Peziza-form Wakker has given the name of Sclerotinia bulborum. The sporidia are binucleate (16 x 8 p). There is one peculiarity about these sclerotia, that when cultivated in a nutrient solution they will form a mycelium and produce secondary sclerotia. It is needless to say that when once a bulb is attacked remedy is hopeless. Onion bulbs are also liable to attack. Garcl. Chron. May 12, 1894, p. 592 ; Mass. PL Dis. 380. Hyacinth Yellow Disease. Pseudomonas Hyacinthi. A disease affecting Hyacinth bulbs has been described under the name of " yellow disease " which appears on them in the autumn, filling the 70 FUNGOID PESTS OF CULTIVATED PLANTS. vascular bundles with a yellow slime. This mucus is said to contain immense quantities of a bacterium, to which at first the name of terium Hyacinthi was applied. 'Whilst these little hodies are emhedded in the slime they remain motionless, hut when removed from it they soon exhibit a lively motion, and begin to divide. In the spring they appear in the vascular bundles of the leaves. Gard. Chron. May 12, 1894, p. 592; Journ. B.H.S. xxvi. 1901, p. 222 ; Hart, J Som. Dis. Tr. p. 37. Another disease attacks principally the flowering parts and is attended by the production of a foul-smelling mucus. Upon making a close examination Dr. Heine discovered that the mucus and the tissues were full of bacteria, quite different from those of the "yellow disease," and was called Bacillus Hyacinth i scpticus. It is reported that when healthy plants are inoculated with this the evidence of infection is manifested within twenty-fouf hours. When cultivated on Potato it formed a yellow slimy layer, and in a few days gave off a strong offensive smell. Gard. Chron. May 12, 1894, p. 592. Tubeuf contends that a common large Pcziza, which grows on manure heaps {Pcziza vesiculosa), attacks Hyacinths and other plants in gardens and kills them. Mass. PI. Dis. 1G2. COXVALLARIA BROWN Sl'OT. Srptoria brunneola (Fries), PL V. fig. 87. This leaf-spot is found, not uncommonly, on living or fading leaves of Lily of the Valley, but not often in fruit, so that the spots remain sterile ami harmless. It is believed, however, to be only a prelude or early stage of a more highly developed fungus {Splnerella brunneola). Brown irregular spots on the leaves, which at length acquire a blackish colour, precede tin receptacles of the Septoria, which latter subsequently app' ittli dots clustered upon the spots. The sporules are long and tho iadlike, without division (75 100x2/*). This para -in- i- known also in Sweden, Italy, and Moravia. S ' ■ . Syll. 81 1:; : ■>■ urn. L'.lf.s. SX vi. 1901, p. cxl. < "\\ \i.i.\i;i \ Red Spot. Phyllosticta omenta (Fries). Another leal ipol has been found in Britain on leaves <>f Solomon's i. forming oblong blood-red spots with a pallid centre, upon which tin- receptacl* ■ an scattered. The sporules are 3omewha1 Bausage-shaped, roundi d al the end -. and curved 1 i Hi • •">:, <;!, /<). Tin- -pot baa also been Found in Prance, Belgium, Germany, Italy, Portugal, Siberia, and North America. Sacc. Syll. Lii. 824 , Grevillea, \i\. p. 71, No. 187. FUNGOID PESTS OF CULTIVATED PLANTS. 71 Lily of the Valley Cluster-cups. JEcidiu?n Convallarue (Schum.), PI. V. fig. 81. The Lily of the Valley is very rarely attacked by this parasite in Britain, although it is occasionally seen ; but on the Continent it has the reputation of being a destructive pest. No Uredo form or teleutospores have yet been affiliated to this species of cluster-cup. The cups are clustered together on paler spots of the leaves, chiefly on the upper surface, and the white fringed cups are filled with bright orange fecidiospores, presenting under the microscope the most elegant appear- ance. The ascidiospores are globose, minutely warted (20-25 /.< diam.). It is to be hoped and anticipated that remedial measures will not be called for. The area of distribution includes Belgium, Germany, Hungary, Finland, and North America. Gard. Chron. July 5, 1884, with figs. ; Grevillea, xiv. 2 ; Sacc. Syll. vii. 2915 ; Ploicr. Brit. Ured. 264. Snowdrop White Mould. Botrytis galanthina (B. & Br.), PI. VI. fig. 88. This mould appears to have first been made known in 1873, when it was detected on the bulbs of Snowdrops, attacking the outer coats and destroying them. At first it threatened to become very destructive in the North, but has never given much trouble in the South. The threads of the mould are shortly branched in the upper portion turning brownish. The branches are somewhat thickened upwards, bear- ing the obovate spores in clusters about the apices, each spore or conidium being seated upon an elongated spicule. The conidia are hyaline and subglobose or obovate (15-18 x 10-11 p). The mould attacks also growing plants, as soon as leaves and flowers appear above ground, stopping the flowering and the proper development of the leaves. Then a delicate white mould is seen to cover the leaves and spathes. Later on numerous minute black sclerotia are formed in the tissues of the decaying leaves and the outer bulb scales. Some impetuous author has called this fungus Sclerotinia galanthina before a single cup of the Peziza has ever been seen, or existed, except in his own fertile imagination. We do not intend to follow him into fairy- land, but adhere to the Botrytis until it falls away. Massee calls the mould Botrytis ciuerea, and the Peziza Sclerotinia Fucheliana.* (See fig. 10.) Ann. Nat. Hist. 4th series, xi. p. 346 ; Grevillea, ii. 139 ; Gard. Chron. Mar. 2, 1889, p. 275 ; Mass. PI. Dis. 159 ; Sacc. Syll. iv. 705. Crocus White Mould. Botrytis Croci (Cke. & Mass.). This mould was found, upon the dead leaves of Crocus in the autumn of 1887; but it is just possible, acknowledging its relationship, that it * Journ. R.H.S. xxvi. 1901, p. 41, fig. 4, and p. xxxvii ; also 1902, xxvi. p. 731 g. 306. 72 FUNGOID PESTS OF C TITIVATED PLANTS. FlO. 10. D'HI;-, US (iAl.AN 1HIN \, A PaBASITE 'IN Snowdrops. i \ young Snowdrop badly diseased, oat. size. 2. Fruiting branch of the. Botrytu, or summer form of the fungus, x 350. :s. A Bnowdrop bulb with Bolerotia, oat. size, i Isolated solerotia, aat. size. 5. A sclerotiuin bearing a crop of Boirytis, the spring following its formation, < LO. 6. Botrytia oonidia germinating, x 400. 7. An organ of attachment of the Botrytia, x 400. h. Chains of oonidia, of unknown use, formed on mycelium of the Botrytis, x 400. FUNGOID PESTS OF CULTIVATED PLANTS. 73 may not hesitate to attack living plants in the same way as the Snowdrop species. It forms dark smoky tufts, which sometimes unite in a larger effused mass. The threads are comparatively thick and rather closely jointed, attenuated upwards towards the apex, where they are slightly and sparingly branched, downwards of a pale olive colour, but uncoloured in the upper portion. Conidia elliptical, hyaline (15-18 x 8-10 /*), collected together at the tips of the threads, or of the branches, in small glomerules or clusters of from three or four to seven or eight conidia. In this respect the present species appears to be rather peculiar, since the head or glomerule of conidia in most cases contains a large number of individuals. It has to be discovered whether this species is capable of providing itself with sclerotia and of developing therefrom the customary Sclerotinia. Grcvillea, xvi. 10 ; Sacc. Syll. x. 7165. Copper Web. Bhizoctonia Crocorum (DC). Amongst the diseases to which the Crocus, especially the Saffron Crocus, is subject is one which has long been known under the name of " copper web." This is due to the presence of a parasitic fungus which lives and thrives at the expense of the Crocus corm. The fungus was classed amongst the Truffles by Duhamel in 1728 and afterwards figured by Bulliard under the name of Tuber parasiticum, which was afterwards changed by Persoon into Sclerotium croceum; but it was De Candolle who finally raised it to the dignity of a genus and called it Rhizoctonia. This singular parasite consists of Sclerotia-like tubercles united by byssoid filaments going from one to the other and forming a sort of sub- terranean web or net. It is by means of these filaments, which are attached to the rootlets of the plant or which creep over the surface of the bulbs after having pierced their integuments, that the parasite appropriates their nutritive juices after the manner of the "Dodder," and induces, if not direct death, at least a weakly development. It was doubtful for a long time whether any real fructification was produced ; and even now it is uncertain, although Broome found, on what he considered the same web on Mint, not only the hard warts, but little tawny tufts of a looser texture covered with globose or ovate spores. It seemed evident that the tufts and warts were forms of each other, but whether the spores were the true fruit, or only a secondary form of fruit, has not been determined. Journ. B.H.S. vol. v. 1850, p. 23. Narcissus Brand. Puccinia Schroeteri (Pass.), PI. V. fig. 89. The leaves of Narcissus have recently been found in this country to be affected with a disease which apparently originated in Italy and after- wards extended into Germany. The spots are large and oblong, with a tawny-violet border; the pustules are produced on these spots, and either solitary or a few together, cither covered with, or girt by, the remains of the ruptured epidermis. 74 FUNGOID PESTS OF CULTIVATED PLANTS. No -T.'cidiinu or Uredo has been found associated with this disease. The teleutospores are somewhat elliptical, from golden-yellow to chest- nut-brown (38-60 x 24-27 /*), obscurely reticulated, either rounded at both ends or with the base somewhat attenuated into the very short, thick, deciduous peduncle, with a central partition dividing the teleutospore into two nearly equal cells. Nuovo Gioni. Bot. Ital. vii. 255 ; Sacc. Syll. vii. 2579. The attack of Fusarium bulbigewum on Narcissus bulbs (Grevillea, xvi. 49) has not been repeated. A form of leaf-spot (Septoria Narcissi), with the receptacles scattered over the tips of fading leaves, has not yet been observed out of Italy. Iris Rust. Urcdo Iridis (Thiim.). This rust is believed to be common in gardens on the leaves of various species of Iris and to be quite distinct from another Uredo which furnishes the uredospores of Puccinia Iridis (DC). This Uredo is supposed to have neither JEcidium nor Puccinia associated with it. The pustules are linear-ovate, and sometimes confluent, on both sur- faces of the leaves, covered at first by ihe cuticle and then exposed by rupture, of a chestnut-brown colour. The uredospores are almost globose, rarely somewhat pear-shaped, externally rough, brown (30-35 x 20-25//). Dr. M. Foster says "it does not readily attack the broad-leaved Mediterranean forms, but I am inclined to think that almost every species would take it." Syll. xi. 1299 ; Ploicr. Brit. Ured. 257. There is supposed to be another species in North America (Uredo iridicola) on the leaves of Iris versicolor, with rough globose uredospores 25 /< diam.), of which we know nothing, and it may be the Urcdo Iri - 1(5 2(5 p), externally rough, and ochi Tin- beleuto pon occur in linear, elongated, striaaform pustules, which art blackish to the eye ; the spores are two-celled, club-shaped, with the apex rounded, or rather obtuse, or acuminate, with the spore-coat thickened at tin apex, constricted in the middle at the septum (80-55 x 14-22 /j), smooth, pale brown, with a hyaline pedicel (12 x 5 /<). • FUNGOID PESTS OF CULTIVATED PLANTS. 75 This species is known in France, the Ardennes, Germany, Switzer- land, Italy, and Siberia. No associated cluster-cups are known. Sacc. Syll. vii. 2284 ; Cooke M.F. p. 203 ; Hdbk. No. 1466 ; Plowr. Brit. Ured. 190. Cluster-cups (JEJcidium Iridis) are known in North America on leaves of Iris versicolor. Iris Leaf-blotch. Hetcrosporium gracile (Wallr.), PI. V. fig. 90. One of the most persistent and troublesome of Iris diseases is this mould, which appears at some seasons with astonishing vigour upon the leaves of Iris germanica and other species. The upper portion of the leaves turns brown and decays or rots, and some plants are soon killed ; large dark spots, becoming black, rounded, or elliptical, from half to one inch in length, with a brown border, appear on the brown parts, or on the still green leaves, velvety with the parasitic mould. In other cases the spots are smaller and more numerous, with a narrow brown margin, and simply bleached or dead tissue, on which are sprinkled a few tufts of the mould. The mould consists of rather short and thick jointed threads in small tufts, and of a sooty-brown colour, bearing singly, or nearly always, the conidia of variable size, some of which are elliptical and without division, whilst others are elongated, and once or twice divided transversely into cells (35-70 x 14-20 ju), and also of a smoky colour, the surface rough with minute points. This disease seems to be known in France, Germany, Italy, the Cape of Good Hope, New Zealand, and North America. If not too firmly established, syringing with one of the copper solu- tions may be of some service ; but the conidia germinate freely at every joint, and if not destroyed will quickly spread the disease. Gard. Ghron. June 9, 1894, p. 718; Sacc. Syll. iv. 2308; Joum. B.H.S. xxvi. 1901, p. 450. Reported also on Narcissus, Joum. R.H.S. xxviii. 1904, p. G79. Ieis Bulb Scab. Mystrosporium adustum (Mass.), PI. V. fig. 92. Bulbs of Iris reticulata have lately been affected and frequently destroyed by the incursions of a black mould, previously unknown, and which forms black crust-like patches on the outer sheath, gradually speading to every part. There is a profuse dark mycelium, from which arise the short branches bearing the large and much-divided conidia. These latter are elliptic- oblong or ovate, with obtuse ends, and from five to seven transverse septa or divisions, which are again subdivided by longitudinal septa in a muriform manner. The, divisions are often oblique, and sometimes with- out longitudinal divisions (45-60 x 20-22 /<), smooth, dark brown, and semi-translucent, produced at the tips of the threads, or at the ends of short branches. 76 FUNGOID PESTS OF CULTIVATED PLANTS. Soaking the bulbs for two hours in a solution of one part formalin to three hundred parts of water will destroy the fungus, so long as it is external and has not penetrated deeply into the bulb. Mass. PL Dis. 325, 411. Leaf spots of six different kinds are recorded on Iris leaves in different countries, but none of them have yet been reported as British. A Bacterial disease on Iris is noticed in Journ. B.H.S. xxviii. 1904, p. 6G2. Gladiolus Smut. Urocystis Gladioli (Smith), PI. V. fig. 94*. This smut, which in some respects resembles that of Colchioum, attacks the corms of Gladiolus, forming the spore masses within the corms. These are in rounded balls, or glomerules (40-50 /« diam.). The teleutospores, or central fertile spores, are rounded on the outer side, but angular by compression elsewhere : they are dark brown (4-6 /*) and smooth. Externally in the glomerules are a series of colourless sterile spores or conidia, as in most other species of Urocystis, and in this case they are very numerous and evenly distributed. The glomerules, or spore masses, have somewhat the appearance of lar^e spores, divided in different directions, but in reality they consist of an agglomeration of smaller spores, closely compressed together into a ball, the inner ones being coloured and capable of germination, the outer incoloured and sterile. When fully matured the component cells 3( parate under pressure, but the true function of the sterile cells has not been determined. It might be advisable to immerse any suspected corms for a time before planting in Condy's fluid ; but it is hopeless to expect any remedy wIkd the corms are seriously attacked. Known also in France and Germany. Gard. CJvron. Sept. 30, 187G, p. 420, fig. ; Grevillea, v. 57 ; Sacc. Syll. vii. 1900 ; Mass. B.F. 187 ; Ploicr.Br.' Urcd. 2H7 ; Cooke M.F. 232. Gladiolus leaf-spot (Se/itoria Gladioli) and Gladiolus rust (Puccinia m in present unknown in Britain. ( Colchn i m Smut. Urocystis Colchu i (Schl.), PI. V. fig. 91. This is a di i of Colchicum which lias long been known and too prominent in it- manifestations to escape notice. The growing leaves are the subject <>f attack, and these are distorted and disfigured by the long and uglj pustules formed by tin pest. These are large, thick, swollen, or bullate, at first covered by the epidermis, hut at lengtb ruptured and fringed with the remains of the torn cuticle, exposing the black, sooty- Looking mass of complex jpon . The "101111 rul< -. or clusters, are nearly globose (20-33 x 1G-20/i), with tie central poo- few and eliestmit-lirown, Compi '( -■ d at the points of FUNGOID PESTS OF CULTIVATED PLANTS. 77 contact (10-15 ^u). The sterile spores of the circumference are pale, some- times in two strata, and also compressed where they come into contact (7-11 [x diam.). When mature the spores are sprinkled about over the foliage in an unsightly manner. The disease is liable to attack species of Scilla and Muscari if found in proximity. Spraying the plants early with Condy's fluid has proved to be preventive. Known in Italy, Belgium, and Germany. Sacc. Syll. vii. 1895; Mass. PL Dis. 227, 404; Cooke M. F. 232; Mass. B.F. 186 figs. 86, 87 ; Cooke Hdbk. No. 1539 ; Ploivr. Brit. Ured. 286 ; Card. Chron. Sept. 30, 1876, fig. Colchicum leaf-spots are also known in Italy and France. Colchicum Rust. Uromyces Colchici (Mass.), PI. V. fig. 93. At present this is solely a British product, and has for three successive seasons completely destroyed a bed of Colchicum speciosum, and has latterly attacked plants of C. bavaricum and C. autumnalc growing in the neighbourhood. The parasite attacks the leaves, commencing at the base of the leaf- sheath, and gradually extending towards the tip of the leaf. The oldest leaves are the first to be attacked. The pustules are large for the genus, and often elongated on the sheaths, whilst upon the leaves they are liable to be collected in circular groups. They remain for a long time covered by the cuticle, which is finally ruptured to set the teleutospores free. Teleutospores broadly elliptical or subglobose, with the apex slightly prominent, epispore, or spore coat smooth, dark brown, and as much as 2/x thick (28-38 x 21-28 /*) seated upon a hyaline persistent pedicel. Cluster-cups or Uredo unknown. No remedy has been proved to be successful. Grevillea, xxi. 6 ; Mass. PL Dis. 226, 406. ■ The species of Veratrum are very subject to parasitic diseases in North America. Dracontium Cluster-cups. JEcidium Dracontii (Schwz.). These cluster-cups are found in gardens on the leaves of Arum tri- phyllum, and were first made known in the United States. The spots on the leaves are pallid and broadly extended, sometimes occupying nearly the whole leaf. The cups are rather large and distinct, being scattered without order over the spots, and not clustered as in JEcidium Ari. The secidiospores are subglobose and of orange-brown colour, somewhat angular by compression and minutely rough (15-16 fj. diam.). It is scarcely probable that remedies will have to be sought after for 78 FUNGOID PESTS OF CULTIVATED PLANTS. this species, as its appearance will now be problematical after so many years of absence. Cooke Hdbk. No. 1611 ; Sacc. Syll. vii. 2962 ; Plowr. Brit. Ured. 266. The ordinary Arum cluster-cups found on the leaves of wild Arum maculatum, and another species (JEcidium a/roideum) which occurs in Natal, are apparently quite distinct. Calla Soft Eot. Bacillus Aroidece (Town.). This disease has recently been investigated in the United States, and declared to be Bacterial. The same organism is declared to be capable of attacking a large number of vegetables. It occupies the intercellular space in its host, and dissolves the layers which connect the cells, causing the tissue to break down into a soft slimy mass. No successful treatment discovered. Journ. B.H.S. xxix. 1905, p. 761. FERN DISEASES. The diseases of hardy Ferns under cultivation in this country are very few and unimportant, although several are recorded abroad. Damping off. Pythium intermedium (De Bary). The " damping off" of the prothallia of Ferns is possibly sometimes due only to an excess of moisture ; but an actual disease has been recog- nised in the United States, and there is no reason why ic may not make its appearance amongst us, as the fungus itself is of European origin. The affected prothallia become quite soft and limp, and darker in colour than the healthy ones. An allied species of fungus is responsible for the " damping off " of seedlings of crucifers, Avhilst some authors regard them as the same species. In structure Pythium resembles a Mucor, and produces resting spores as the result of conjugation, similar to the rot-moulds. Bull. U.S.A. Exp. St a. Cornell Univ. 94, p. 247, pi. ; Bot. Zeit. 1881 ; Sacc. Syll. xi. 1400 ; Mass. PI, Bis. 350. Fern Rust. Uredofilicum (Desm.), PL IV. fig. 79. There are two or three kinds of Fern rust known, but only one species appears to be known in Britain, and that is not uncommon in gardens and greenhousi . i pecially on Cystopteris fragilis, appearing on the under side of the fronds, which consequently assume a sickly appearance. The I* are rounded or irregular, and scattered over the under surface of the fronds in bright yellow spots. The uredospores are powdery, and are of two forms, the one ovate or elliptical and spinulose above, but smooth below (22-85 x 18 20 /u), the other somewhat angular with a thick FUNGOID PESTS OF CULTIVATED PLANTS. 79 smooth outer coating (26-38 x 18-29 /t), and both of a bright orange colour. Ferris on which the rust makes its appearance should be isolated, and the diseased fronds cut off and burnt, whilst the plants so left should be sprayed with Condy's fluid. It is distributed through Belgium, Germany, Finland, Austria, Bohemia, Italy, South Africa, and North America, and appears to be the same as Uredo Polypodii (Pers.). Sacc. Syll. vii. 3096, xi. 1304 ; Cooke, M.F. 112 ; Proc. Amer. Acad. 1894, p. 396 ; Cooke Hdbk. No. 1569 ; Plowr. Brit. Ured. 256. Uredo Aspidiotus in the United States appears to be different, as also Uredo Pteridis in California, and Uredo Scolopendri in Germany and the Netherlands. PESTS OF GARDEN VEGETABLES. The majority of the pests which infest garden vegetables, salads, and sweet herbs are specifically distinct from those which attack garden flowers, but are equally prevalent and destructive. As, however, they are closely allied, the treatment and remedies will be found to be, in most cases, the same. It cannot be urged too often that, as prevention is better than cure, the greatest care should be taken against the introduc- tion of fresh diseases into the kitchen garden, and any encouragement to the permanency of old ones. Wild plants — or "weeds," as they are termed — are many of them subject to fungoid diseases, which may transfer themselves to kindred cultivated plants when growing in their vicinity. As a warning to careless cultivators, wild Cruciferous or Composite weeds should not be permitted to invade the garden or its borders. Further- more, the "rubbish heap," in an out-of-the-way corner, should be dis- pensed with, because the resting spores, or the winter condition of some of the most troublesome pests, will be found in the stems or other dead parts which are usually consigned to a rubbish heap instead of being burnt; and consequently the "rubbish heap" becomes a teeming emporium for the dispersion of active spores in the spring, so that from this centre a very large area may speedily be infected. Cabbage Leaf- spot. Phyllosticta Brassicce (Curr.), PL VII. fig. 95. Cabbage leaf spotting is not a serious calamity, but it may become annoying when excessive. The most common spot is that above named, which occurs also on rape. The spots are generally rather large and bleached, becoming white on the upper surface. The receptacles are very small and numerous, chiefly towards the centre of the spots. The sporules are ovoid, with two nuclei (5 /j long) expelled from the mouth of the receptacle, when mature, in small rosy tendrils. It is known also to occur in France, Belgium, and Portugal. 80 FUNGOID PESTS OF CULTIVATED PLANTS. Seldom of sufficient importance to demand a remedy, but in such case spraying of young plants might be beneficial. Sacc. Syll. iii. 207. Another species (Phyllo'sticta Naju) is known in France, but is very little different in appearance, and a slight difference in the form of the spo rules. A leaf-spot with two-celled sporules {Ascochyta Brassicce) is known on the Continent, forming large irregular bleached spots, on which the receptacles are densely crowded. The sporules are fusiform, septate and nucleate (15-16 x 3-4 yu). Cabbage Anthracnose. Glwosporium concentricum (Grev.), PI. VII. fig. 96, sporules. In 1851 attention was called to this parasite by a memoir in Journal R.H.S., in whicb it was stated that the fungus was discovered by Dr. Greville thirty years previously, but never constituted itself a pest until the former year. It forms on both surfaces of the leaves of Cabbage and Cauliflowers, roundish, often confluent, patches, consisting of little white specks disposed more or less concentrically, those of the centre frequently becoming yellow, and at length fading away. The sporules are developed beneath the cuticle, and are oblong and cylindrical, often curved, containing two or three nuclei (about 20 x 7 /.t) borne upon short delicate spore-bearers. These sporules are mixed with a viscid fluid, and in dry weather ooze out through the fissures in the cuticle as rude irregular tendrils. There is no trace of a perithecium, only a subcuticular cell, in which the sporules are developed. The tendrils are dissolved with moisture, and the sporules are disseminated over the leaves. This fungus has also been found in Germany, but nowhere has it become a troublesome pest, and, as far as we can learn, is only an occasional visitor. Sacc. Syll. iii. 3665; Joum. R.H.S. vol. vi. 1851, p. 117, with fig.; Cooke, Hdbk. 1408. ._ There appears to be no chance of discovering what Ccrcospora Bloxami B. and Br. can be. It was imperfectly described, and the supposed original specimens have no fruit (PI. VII. fig. 97). Cabbage White Rust. Cystopus candidus (Pers.), PL VII. fig. 98 a, b. This is a very old and very common offender, and is not confined to Cabbages, but extends its ravages to almost any Cruciferous plant. It was described by Berkeley in 1848 as White Bust, and was then believed, and long afterwards, to be related to the ordinary rusts, but recently, when better known, it has found a place near tho Rot Moulds. The external appearance consists of swollen, convex, white pustules, FUNGOID PESTS OF CULTIVATED PLANTS. 81 sometimes in rings and patches, and sometimes scattered over all the green parts. At first the cuticle is shining and unbroken, but at length it is irregularly ruptured, to permit the spores to escape. The base of these pustules consists of a mass of irregular, thick, knotted, mycelium, from which arise club-shaped cells, bearing a chain of globose spores, slightly attached to each other, and forming a kind of necklace, the upper one falling away, and then the next, and so on in succession, as they become matured (12-18 n diam.). Each spore or conidium when placed in water or a damp situation undergoes just such a change as we have already described for the conidia of the Rot Moulds (see Introduction, p. 2). From five to eight zoospores are formed in the interior, and escape by rupture of the wall of the conidium. Thus each conidium produces from five to eight active zoospores, which finally serve to disseminate the parasite by infection. In the same manner also as in the rot mould does the internal mycelium produce resting spores, which, after a period of rest, probably through the winter, develop numerous active zoospores in the spring. In the present species the resting spores are globose (30-50 /j. diam.), externally warted with large obtuse warts, and of a brown colour. This pest is distributed throughout Europe, and many parts of Asia, Africa, and America. It may truly be said to be cosmopolitan. Sacc. Sijll. vii. 792 ; Mass. PL Dis. 59 ; Smith, Field Crops, 86 ; Cooke, M. F. figs. 198-200; Cooke, Hdbk. No. 1564; " White Bust," Journ. B.H.S. vol. iii. 1848, p. 265, with figs. ; Tubeuf, Dis. 123. Cabbage Black Mould. Alternaria Brassicce (Berk.). This black mould was first described by Berkeley under the name of Macrosporium Brassicce, and was found by him growing on Cabbage leaves in company with the common Cladosporium herbarium, of which he considered it to be probably a condition. The conidia are clavate, and divided by from five to eleven septa, some of which have longitudinal divisions, and are of an olive colour (60-80 x 15-16 /x). Subsequent examination seems to have shown that the conidia are produced in short chains, attached end to end, as is the case in Alternaria, and hence the change of name. It is evidently very rare as a garden pest, although it has also been found in France and Italy. The mould is developed on dry spots of dead tissue ; on Cabbage leaves, and may probably be only a saprophyte, which we have never seen, and probably it has not occurred in Britain again during nearly half a century. Tubeuf, Dis. p. 518 ; Cooke, Hdbk. No. 1733 ; Sacc. Syll. iv. 2613. Cabbage Rot Mould. Peronospora parasitica (Pers.), PL VI. fig. 30. Sometimes found in company with the " white rust," and often independently, on the leaves of many Cruciferous plants. We have already introduced this mould in the " Pests of the Flower Garden " (p. 21), where it is far less troublesome and dangerous than here, G 82 FUNGOID PESTS OF CULTIVATED PLANTS. and to that account we have nothing to add, heyond the intimation that this disease partakes essentially of the characters of the well-known Potato disease, and that whatever remedies may have been applied with success in one instance are likely to avail in the other. The only fungicide which has been recommended for use in the early stages of this disease is diluted Bordeaux mixture, but of course this will be of no avail where the mould is well established and the mycelium has penetrated deeply into the tissues of the host-plant so that the resting spores are in course of formation. In such case the only alternative is to prevent the spread of disease by destroying all affected plants which may contain resting spores. Known through the whole of Europe, the greater part of America, and in Asiatic Siberia. For development of " rot moulds " see Introduction, p. 2. Sacc. Syll. vii. 830 ; Mass. B. F. 119 ; Mass. PL Dis. p. 79 ; Smith, Field Crops, 86 ; Gard. Chron. Nov. 17, 1883, figs. 109-111 ; Cooke, M. F. f. 265 ; Cooke, Hdbh. No. 1778. Damping off. Pythium De Baryanum (Hess.), PI. IX. fig. 99. This disease affects seedlings of Cress, Mustard, &c, when the plants fall over and die oil', as a result of the destruction of the fundamental tissues by the attack of this parasite. The stem fails just above the sur- face of the ground. The mycelium is branched, with the lateral branches thin and reflexed. The conidia are globose, with thin walls, often terminating the lateral branches (20-30 p). The resting spores, or oospores, are also globose, with a thick smooth outer coat (25-35 /i) resulting from the conjugation of a club-shaped cell or antheridium with the globose cell which after- wards becomes the resting spore (fig. 99 a). In many features of their life-history these fungi, called Ptjthium, resemble the rot moulds, and especially in the production of zoospores. The resting spores, however, are produced externally, and not within the tissues of the host plant. This disease only occurs in very damp situations, and should be pre- vented by i/ood drainage. Sacc. vii. <)2J ; Ward, Dis. p. 38, figs. 5-9 ; Mass. PL Dis. 54, fig. 4 ; Quart. Journ. Micr. Sci. xxiii. p. 4h,, \rella hmssic(ecola (Duby.), PL VII. fig. 100. This affection of the haves is hold to bo the mature condition of tho leaf-spot, which occurs earlier in the year. The leaves are disfigured by FUNGOID PESTS OF CULTIVATED PLANTS. 83 large and rather rounded or irregular bleached spots, upon which the perithecia, or receptacles, are scattered, but larger in size generally. The fructification is more complex, since, instead of naked sporules, the recep- tacles enclose long transparent vesicles called asci, each one of which contains eight sporidia. In this species the sporidia are oblong, and divided in the centre into two cells (18 x 4 /<). The mature stage of this pest, in the form of Sphcerella, is not reached until the leaves have lain some time on the ground. This condition of spot has also been found in France, Belgium, Ger- many, and Italy, but is nowhere very common. It is scarcely likely to give more trouble than to pick off and burn the diseased leaves of the Phyllosticta form, as they appear. Sacc. Syll. i. 1989. Ci-UB Root. Plasmodiophora Brassicce (Wor.), PL IX. fig. 101. Club Root is so well known, not only in Turnips but in Cabbages and other plants of the family, that no detailed description is necessary. It is now admitted that the disease is caused by a kind of slime fungus, which occupies the club. It commences early in the growth of the plant affected. The rootlets are swollen in a spindle-shaped manner, usually with a smooth surface, and the plant presents a sickly appearance. At first the cells of the clubbed roots are filled with a yellowish slimy sub- stance which is the early condition of the fungus. Later on this sub- stance will be seen to have undergone a change into myriads of minute spherical spores. During winter these spores remain quiet, but in spring they ripen and prepare for germination. This is done by the gradual conversion of each spore into an active motile zoospore, and each atom, being free, is capable of moving as it pleases by aid of its whip-like tail in any film of moisture. When the motion ceases, these bodies coalesce into a small slimy mass, which in turn coalesces with other masses until a large mass is formed. These viscid masses are washed out of the tissues by early rains, and move about in the moisture by pushing out little portiens of their sub- stance like legs. In this manner they come into contact with the roots of seedling plants, and the disease is communicated. The application of quicklime destroys the germs in the soil. Thirty- five bushels per acre is enough to arrest the disease. Sacc. Syll. vii. 1568 ; Smith, Field Crops, p. 94, figs. 34-39 ; Ward, Dis. PI p. 47 ; Mass. PL Dis. p. 334 ; Journ. R.H.S. xxvi. 1901, p. 190, xxvi. 1902, p. ccxix ; xxviii. 1904, p. 636 ; Tubeuf, Dis. p. 524. Black Rot of Cabbage. Pseudomonas campestris (8m.). This disease, long known in America, has now appeared in Britain. It may appear on the plant at any period of growth. Dwarfing, or one- sided growth of the heads, or absence of head is a symptom. If the stumps of affected plants are broken, a dark ring will be seen, correspond- ing to the woody part of the stem ; in bad cases this blackening may be o2 84 FUNGOID PESTS OF CULTIVATED PLANTS. traced upwards into the centre of the head. In the leaves the symptoms usually hegin at the margins, with yellowing of all the affected parts except the veins, which become brown or black. The disease is caused by a yellow bacterium, which enters the plant above ground, and usually at the margins of the leaves. Slugs and caterpillars may spread the disease by going from diseased to healthy plants. Rotation of crops is recommended to rid the soil of the pest. Cruci- ferous weeds should not be permitted in the neighbourhood to harbour the disease. Removal of infected leaves in the early stages of the disease would be beneficial. It should be noted that when diseased cabbages have been converted into manure, such cabbages as have been manured with this material have exhibited the disease. Smith, U.S. Dep. A9. Turnip White Mould. Oidium Balsamii (Mont.), PI. VII. fig. 102. Turnip leaves, and other garden produce, suffer from the incursions of this white mould, which makes its appearance in the manner usual to all of its kind, by spreading a thin white film of mycelium and conidia over the subjects of its attack, like a hoar frost. It first attracted attention on Turnips in 1880, and since that time has not been uncommon. The lowermost leaves are those which are first attacked. From the coating of white mycelium which soon covers both surfaces of the leaf arise the club-shaped branches, or fertile threads, the lower portion usually consisting of three superimposed cells, surmounted by the maturing conidium, or spore, which is of a barrel shape : that is to say, it is cylindrical, swollen a little in the centre, like a barrel, and truncate or flattened at the ends. When mature, this conidium falls, and, pursuant to the custom in this genus, the next joint pursues its growth and conversion into a conidium, in order to follow its predecessor. These conidia germinate very readily when kept moist, the germ tube projecting at one angle. It is most common when a moist September follows a dry August. Dusting with sulphur is one of tbc most effectual remedies in this kind of disease, which cannot but remind us of the Oidiwn Tuckerioi the vine. Smith, Field Crops, 7G, 77, figs. 27, 2H ; Curd. Chron. Sept. 25, 1880. IIokski; vdish Leap-spot. Phyllosticta Armoracia (Cooke), PI. VII. fig. 103. A number of specimens of this parasite were collected in a garden, fully a quarter of a century ago, and distributed, under the name of Septoria Armoracia, when the distinctions between Sc]>t<>rin and I'ln/llosticta were not recognised. The spots and their disposal upon the leaves appear to be precisely the same as in Septoria. The receptacles, or perithecia, are minute and immersed in the spots FUNGOID PESTS OF CULTIVATED PLANTS. 85 The sporules are small, oblong, and colourless (6 x 8-4 /<), and are produced in great quantity. It is uncertain where else this species has been obtained, as we know of no record beyond the specimens above named. The external appearance of the affected leaves is the same in the three species of Phyllosticta, Ascochyta, and Ramularia, as visible to the naked eye. Cooke, Fun. Ex. 32. Horseradish Leaf-spot. Ascochyta Armoracice (Fckl.), PL VII. fig. 101. As already stated, the leaf- spots caused by this disease can scarcely be distinguished from those caused by the Ramularia, except possibly in the recognition of the minute dot- like receptacles which are seated upon the spots. The sporules, which are produced within the receptacles, are oblong, obtuse at the ends, and divided transversely into two cells (18-20 x 3 fx), which is the only apparent distinction between Ascochyta and Phyllo- sticta. This cannot be considered a dangerous or troublesome garden pest, but if its banishment is desired, it would be well to try spraying with one of the copper solutions. The fungus is known in the Khine Provinces, Holland, and Italy. Sacc. Syll. iii. 291 ; Fckl. Sym. Myc. 388. Horseradish Spot Mould. Ramularia Armoracice (Fckl.), PI. VII. fig. 105. This little white mould is common enough on leaves of Horseradish ; although it probably does no harm to the roots, still it makes the foliage look shabby enough. * The spots are at first ochrey-white, then pallid, and somewhat circular, until they run together into a larger blotch. The fertile threads arise from the buried mycelium in small tufts, and are erect and unbranched. The conidia, or sporules, grow singly at the tips of the threads, and are rod-shaped, sometimes a little thickened at the middle, and obtuse at the ends (20 x 4). There is hardly any appearance of mould to the naked eye, or at most only a little mealiness on the spots. Finally many of the decayed spots drop out, leaving holes in the leaves. There is so much external resemblance in the spots caused by this species, Phyllosticta Br assica, Ascochyta Armoracice, Septoria Armoracia, and Sphcerella hrassiccecola, that it is almost impossible to distinguish them one from the other by the naked eye, and all are liable to be found on Horseradish leaves. If applications are considered desirable, then diluted Bordeaux Mixture may be used. Sacc. Syll. iv. 978 ; Sacc. Fun. Ital. 9.86 ; Orevillea, iii. 65. 86 FUNGOID PESTS OF CULTIVATED PLANTS. Bean Eust. Uromyces Fabce (Pers.), PL VII. fig. 106. This extremely common parasite is found on the foliage, stems, and leaves of the Garden Bean (Viria Faba), as well as the Horse Bean or Field Bean, covering them with a rust-coloured powder, which consists of the scattered uredo and teleutospores. The uredospores are first produced, and are the most profuse, bursting through little rounded pustules which elevate the cuticle. They are globose or nearly globose in form, of a yellowish-brown colour, and a roughened or shortly spiny surface (20-30 x 17-20 p). These are ultimately succeeded by the teleutospores, which are of a darker colour, somewhat club-shaped, with the outer coat much thickened at the apex, and terminated by a depressed pore. They are longer and rather broader than the uredospores, and apparently smooth, with a colourless deciduous pedicel (24-27 x 17-30 /.i). This species is known in France, Belgium, the Netherlands, Germany, Switzerland, Austria, Hungary, Bohemia, Italy, Finland, Siberia, South Africa, and North and South America. It is difficult to suggest a remedy when none have proved really successful. How often the bean haulms covered with rust and teleuto- spores arc left in heaps to rot, when it would be much more politic to burn them instead of leaving them to disseminate the disease ! s. c Syll. vii. 1921 ; Mass. PL Dis. p. 229 ; Cooke, M. F. 201 ; Cooke, Hdbk. No. 1512 ; Ploicr. Brit. Ured. 119. . French Bean Rust. Uromyces Phaseoli (Pers.), PI. VII. fig. 107. Uromyces appendiculatus, DC. Changes of names in the Uredines have been so numerous of late years that it would seem a relief to fall back on such an old name as Uromyces appendiculatus again if not forbidden. This rust is found on the leaves of most kinds of garden beans ; what- ever name the cluster-cups may have had, we find the uredospores to be plentiful enough in rounded pustules, of a pale cinnamon-brown. They are either round or shortly ellipsoid (21-33 x 1G-20 /<), with a rough surfac. The teleutospores occur in darker, almost black, pustules to the eye, which are soon ruptured, and the powdery spores set free. These teleuto- spores are either subglobose or elliptical, with the spore-coat much thickened about the apex, surmounted by an obtuse hyaline wart or papilla. Externally the spores are smooth (26-35 x 20-26 /<). It is recorded in France, Belgium, the Netherlands, Germany, Switzer- land, Austria, Eungary, Italy, Portugal, and North America. Spraying with potassium sulphide solution should he commenced as early as possible after the manifestation of the disease, to be of any .ice. There is no hope with the urcdine i when firmly established, and the mycelium permeates the host-plant. FUNGOID PESTS OF CULTIVATED PLANTS. 87 Sacc. Syll. vii. 1926 ; Mass. PL Bis. 230 ; Cooke, M. F. 211 ; Cooke. Hdbk. No. 1543 ; Plowr. Brit. Urecl. 122. French Bean Anthracnose. Colletotrichum Lindemuthianum (Sacc. and Mag.), PI. VII. fig. 108. This disease appears on the legumes of French Beans and Peas, while still living, and often before they are mature, giving them a very unsightly appearance. The spots are roundish, becoming brown, with a reddish margin. The pustules appear in the centre of the spots, raising the cuticle, so that it seems inflated, and then splitting it. The conidia are produced at the tips of threads collected in little bundles, the threads being nearly three times as long as the conidia, which latter are oblong, either straight or curved, rounded at the ends, and granular within (15-19 x 4-5 /.«). . The disease is very prevalent in the United States, where it is reported that " the young fruit is most subject to attack, and if the parasite gains a footing, it is very disastrous, as growth is checked, even when the pods are not conspicuously diseased." A favourable condition is dampness of soil and atmosphere, which seems to be more necessary to the development of this disease than in the majority of others. An airy dry situation for the plants is recommended as the best means of preventing an attack. The application of sulphur is said to check the disease somewhat. Sacc. Syll. iii. 3747 ; Mass. PI. Bis. p. 208 ; Grevillea, x. p. 48 ; U.S.A. Bej). Agri. 1887, p. 361, pi. vi. ; Tubeuf, Dis. 486, fig. Pea Pod Spot. Ascochyta Pisi (Lib.), PI. VII. fig. 109. This spot occurs sometimes upon the leaves but most commonly on the legumes of the Garden Pea, and was first called Bepazea concava on account of the concave little spots on the pods. The spots are round and yellowish, with a definite brownish margin in the centre of which nestle the small brown receptacles in which the sporules are produced. When mature these latter issue in a short thick reddish tendril from the mouth of the receptacle, and sometimes become confluent. When dissolved by moisture the sporules separate and flow over the matrix. They are oblong, divided in the centre into two cells, usually with a small nucleus in each cell (14-16 x 4-6 ^). This disease is recorded in Belgium, Germany, Portugal, and Italy. No experiments have been recorded on the treatment of this disease, but it has been recommended that Bordeaux mixture should be tried if the affection should become troublesome. Sacc. Syll. iii. 2197 ; Berk. Ann. N. II. No. 194, t. xi. f. 3 ; Cooke, Hdbk. No. 1355 ; Mass. PI. Dis. 275, fig. 72 ; Tubeuf, Dis. 472. Saccardo enumerates a species under the name of Ascochyta pisicola, on pea pods ; but surely it can only be the above species, as no specimen can be found in the Kew Herbarium with the other name. 88 FUNGOID PESTS OF CULTIVATED PLANTS. Garden Pea Rust. Uromyces Pisi (Pers.), PL VII. fig. 110. The Pea rust is not so common as the "Pea mildew ", on garden Peas, but it is developed in the tissues, and at length makes its appearance externally by bursting in little pustules through the cuticle of the leaves. The earlier pustules are brown, of a paler colour than the later ones, powdery, and of a rust colour. These uredospores are rather globose, or a little elongated, with a roughened or minutely spiny surface (17 x 24). The teleutospores are produced in similar pustules, but are darker, and of a brownish-black in the mass. They are broadly elliptical, with a suggestion of pear-shape, being narrowed downwards into a long and colourless pedicel (20-32 x 17-21 /<) ; the apex of the spore has the coat, or tegument, a little thickened, and the whole surface is delicately punctate when fresh, but apparently quite smooth when old or dried. The uredospores are much more common on the garden Pea than the teleutospores, which latter are comparatively rare. Those who believe in hetertecism affirm that the cluster-cups of this rust are produced upon the leaves of the Wood Spurge {Euphorbia Gyparissias). This rust occurs in France, Belgium, Germany, Austria, Bohemia, Switzerland, Finland, Italy, Sicily, and Siberia. c. Syll. vii. 1941 ; Cooke, M. F. p. 212 ; Titbeuf, Dis. 334 ; Ploivr. Brit. Ured. 133. Pea Mildew. Erysiphe Martii (Lev.), PI. VII. fig. 111. Everyone with a garden knows the "Pea mildew" too well, the whitened leaves, covered on both sides, as if with hoar frost or a thin coating of whitewash, showing the sickening yellowish leaves beneath. This mildew is very common, especially towards the close of the season, destroying the last crop. Seen by the naked eye the white coating is soon sprinkled with minute black dots which are the receptacles of the final stage. The white coating consists of a rather dense mycelium of interwoven threads so compact as to choke up the stomates of the leaves. Here and there, scattered over the mycelium and projecting from it, are little suckers, or haustoria, which enable the mycelium to retain its hold. At first the threads of the mycelium, which arise as fertile branches, only produce conidia, in chains, of the kind known as Oidium. Afterwards the black dots appear, which are at first orange, then brown, and finally black, seated upon and scattered over the mycelium. These are the rea ptacles, which, when magnified, are seen to be globose bodies, held down by little root-like filaments at the base, while a circle of flexuous threads are disposed about the lower circumference. These receptacles contain the mature fruits of the parasite, which are small colourless, nearly elliptical sporidia, enclosed in transparent sacs or asci, of a some- whiii pear-shape. Kucli receptaeli holds from I to n of these asci, each of which encloses from I to 8 sporidia. When quite ripe the receptacles are split open and the sporidia i scape, and perpetuate the species. FUNGOID PESTS OF CULTIVATED PLANTS. 89 The Hop mildew and the Rose mildew belong to the same family of parasites. These fungi are, in the first instance at least, true epiphytes, making their appearance on the surface of the leaves before there is any infection or disease of the host-plant, and, as such, are more amenable to treatment. Dry weather in the case of these fungi is usually considered as pro- pitious to their development ; hence it follows that wet checks develop- ment, and syringing or watering the leaves in dry seasons is the best moderator of its evil influence. Sulphur is doubtless of considerable service, as it has been in the Hop mildew. Sacc. Syll. i. No. 73 ; Smith, Field Crops, p. 266 ; Cooke, M. F. 220, figs. 237-9. Parsley Leaf-spot. Septoria Pctroselini (Desm.), PL VII. fig. 112. The leaves of the Parsley and sometimes of the Celery are liable to become spotted with this disease. It shows itself scattered over the surface in little spots, which are at first brownish and then bleached, so as to become almost white in the centre. Scattered over these spots are the little dot-like receptacles, or perithecia, which contain the sporules, the spots being already permeated by the mycelium, which produces the dis- coloured spots. The sporules are long and narrow, thread-like, with a row of small nuclei, and these escape when mature, like a small tendril from a pore at the apex of the receptacle (35-40 x 1-2 fi). When the leaves are moistened and the dew is upon them, the little tendrils ooze out and soon dissolve, so that the sporules may be dis- seminated over the leaf. A shower of rain, or watering artificially, may transfer these sporules to other and healthy leaves. This species is recorded as known in France, Belgium, Italy, Germany, and S. America. Sacc. iii. 2876 ; Mass. PL Dis. 270. Celery Brand. Puccinia Apil (Corda), PI. VII. fig. 113. Sometimes the Celery rust finds its way into gardens, where it soon creates mischief, disfiguring the leaves and stunting the plant. It has been proved that it is capable of being introduced through the medium of seed obtained from diseased plants. The appearance of this pest on the foliage is first detected by swollen paler spots, and soon afterwards the cuticle is broken irregularly over each of these spots or pustules, and the brown powdery spores escape from the fissures like snuff and become sprinkled over the leaves. It is customary, in these latter days, to regard the above as one of the forms of Puccinia bullata, but we prefer to retain the above name as a distinction for a definite disease. 90 FUNGOID PESTS OF CULTIVATED PLANTS. The uredospores are paler than the teleutospores, irregularly rounded, and rough (23-38 x 20-2G ft). The teleutospores are comparatively large, elliptical in outline but constricted in the middle, where they are divided into two cells. The lower cell is a little narrowed into the pedicel, which soon falls away. Externally the surface is smooth and of a dark brown colour (80-56 x 17-28 ft). The best plan is to eradicate all the plants as soon as the disease makes its appearance, to prevent the germination of the teleutospores and the dispersion of the rust. Sacc. Syll. vii. 2211; Cooke, Hdbk. No. 1493; Mass. Dis. PI. 250; Ploicr. Brit. Ured. 156; Gard. Ghron. May 13, 1905, p. 293. Parsnip Rot Mould. Plasmopara nivea (Ung.), PI. IX. fig. 114. This rot mould is similar in character and life-history to the other rot moulds of which we have given an outline (Introduction, p. 2). It first affects the leaves, and then the mycelium descends and forms resting spores in the stems and roots. The white mouldy patches appear first on the under surface of the leaves chiefly, forming an internal mycelium from which the bundles of branched threads arise and appear on the surface. These threads are erect, rather shorter than in many species (250 /< long), tapering upwards and mostly once or twice forked in the upper portion, rarely three-forked, with from one to four horizontal branches near the apex, forked at the extremity, with the forked spicules spreading, each point bearing a single conidium or spore. These are nearly globose or ovoid, with a very obtuse projection or teat at the apex (20-25x15-17 /<), granular within and with a slightly tawny tinge. It has also recently attacked Parsley rerely, see Gard. Ghron. Nov. 5, 1904, p. 313. This mould has appeared in France, Belgium, Holland, Germany, Sweden, Lapland, Tyrol, Italy, and N. America. Sacc. vii. 807 ; Smith, Field Crops, 239; Mass. B. F. 113, figs.6G-70; Cooke M. F. ; Gard. Ghron. Dec. 5, 1884, figs. 124, 125; Cooke, Hdbk. No. 1775. Cki.k i;v Spot Mould. Cercospora Apii (Fres.). This black mould is known throughout Europe and North America on leavi oi Celery and Parsnip causing leaf-spots which are at first y< Uowish, then enlarging and turning la-own. In this country it has not yei been developed into a pest. Spots almost circular (4-0 mm. diam.) with the narrow margin Slightly elevated. Tin- mould developed on the under surface! in small brown tufts. The hypb.ro, or threads, arc either continuous or sometimes with one or two divisions (40 <'><) X4-5 p). The conidiaaiv thin, obclavate, or attenuated upwards, with from throe to ten transverse divisions (60-80 X I /') almost colourless. The variety on Parsnip is known in the United States and Siberia. FUNGOID PESTS OF CULTIVATED PLANTS. 91 That on Celery occurs also in Germany, Austria, Italy, and the United States. Sacc. Syll. iv. 2125 ; Tubeuf, Dis. 514 ; Sacc. Fl. Ital. t. 667. Lettuce Rot Mould. Bremia Lactuca (Regel.), PI. IX. fig. 115. The mould which causes this disease appears to have been known since 1843, but it was in 1846 that Berkeley first drew attention to the pest, and considered the mould to be the cause of the rot. Afterwards it came to be known under the name of Peronospora gangliformis which has since been abandoned in favour of the above name. There is an abundant mycelium present in the leaves before the mould appears on the surface. This is thick and coarse, being furnished with a number of club-shaped suckers or haustoria. From the mycelium arise the erect fertile threads through the natural orifices of the leaves. These are flattened, and from two to six times forked, without cross partitions. The tips of the final branchlets are swollen in a peculiar manner, supposed to resemble "ganglia." These swellings are somewhat of a saucer-shape, with a single spicule in the centre and three or four more growing around the edge. Each spicule bears a nearly globose spore, with a very minute teat or papilla at the apex (16-22 x 16-20 /<). The resting spores are produced in clusters, and are plentiful in old and decayed stems. They are nearly globose, not quite even, and of a tawny colour, exceeding in size the largest dimensions of the conidia (28-34 H ). Found chiefly throughout Europe and in the United States. For Lettuce rotting in greenhouses see Journ. B.H.S. xxvi. 1901, p. 558. Sacc. Syll. vii. 243 ; Cooke, M. F. t. 14, f. 265 ; Tubeuf, Dis. p. 131 ; Smith, Field Crops, 289; Mass. PI. Dis. 74; Mass. B. F. 115, figs. 64, 65 ; Cooke, Hrfbk. 1777. Lettuce leaf- spots are known abroad, and anthracnose in the United States. Potato Spindle Mould. Fusarium Solani (Mart.), PL VIII. fig. 116. Because this parasite was so commonly found upon Potatos in decay it was for a long time supposed that it was only a companion of the Potato murrain, or a consequence of decay. Latterly it has been closely watched, with the conclusion that it is really a destructive fungus on its own account, and will attack stored Potatos, whether bruised or not. It grows either in company with the rot mould or also independently upon tubers which exhibit no trace of decay. The mycelium is similar in both, but the resulting moulds are different. The fruiting threads of the Fusarium or "spindle mould" are shorter, ami for the most part unbranched, bearing at their tips the fusiform or spindle-shaped spores or conidia, which are a little curved, and set rather obliquely upon the threads (40-60 x 7-8 fx). Each sporule is divided by transverse 92 FUNGOID PESTS OF CULTIVATED PLANTS. partitions into four cells, which remain for a long time attached to each other, hut ultimately separate and each segment becomes practically a separate germ cell. Sometimes each of the four cells will commence germination while still attached to each other, but will ultimately fall away, and each cell, now almost quadrangular, will when free assume gradually a spherical shape. They do not always germinate at once, but seem to be capable of an interval of rest of from two to three months. Germination proceeds rapidly, and may be completed in six hours. The mycelium has a putrefactive action, breaking up the cells of the host and hastening decay. Known in Belgium, Italy, and North America. Sacc. Syll. iv. 3386; Smith, Field Crops, p. 32, figs. 10, 11; Mass Dis. PL 333, 442 ; Cooke, Hclbk, No. 1870 ; Jouni. B.H.S. xxix. 1904 p. 141, figs. 27, 28 ; xxix. 1905, p. 873. Potato Scab. Sorosporium Scabies (Fisch.). Nearly fifty years since Berkeley called the attention of the Horti- cultural Society to one of the causes of scab in Potatos, under the name of Tubercinia Scabies. But it was probably known to Martins three years previously. There are some even now who think that Berkeley made a mistake. He attributed the fungus to be closely allied to the smuts, and described it as consisting of globose bodies, composed of minute cells, in such a manner as to form a hollow globe, with one or more lateral openings. " The fungus grows beneath the cortex of the tuber, where it forms a thin dark greenish-brown stratum, often extending over the greater part of the external surface of the tuber." It is said that no trace of the fungus is often to be seen at the time of harvesting, but frequently shows itself during winter in stored Potatos which on digging appeared to be quite sound. In bad cases discoloured spots first appear, and these increase in size and become confluent until at length the entire skin is discoloured. Then the cuticle bursts and the spores are set free. We have ourselves met with such scabbed Potatos in greengrocers' and obtained from them the hollow bodies described by Berkeley, the c\i ti ii' i of which has been called in question. Berk. Journ. B.H.S. 1846, p. 33, figs. 30, 31 ; Sacc. Syll. vii. ; Smith, Field Crops, 35; Mass. PI. Dis. 225; Cooke, Edbk. No. 153G; Plowr. Brit. Ured. 294 ; Journ. B.H.S. xxix. 1904, p. 145. American Potato scab caused by Oosjiora Scabies is quite a distinct thing.- Mass. PI. Dis. p. 299. Potato Tumour. (Edomyces leproides (Trabut.). This disease made it- appearance in this Country in 1901, when a whole crop of Potatos was destroyed by its ravages, and it has since FUNGOID PESTS OF CULTIVATED PLANTS. 93 appeared in other districts. At first it was called on the Continent by the name of Chrysophlyctis cndobiotica (Schilbersky), and was supposed to be an entirely new type of disease, but afterwards when specimens were brought to the notice of Dr. Magnus, he determined that it was the same fungus as that which caused tumour on Beetroot, and hence should retain the name of (Edomyces leproides. The Potatos when attacked are soon either wholly or partially swollen on the surface in a tuberculose manner, turning blackish, and presenting in cells beneath the cuticle a mass of large oval conidia, of a brown colour, with a short hyaline pedicel, which is swollen about the centre. Altogether the disease presents the same features as when it occurs on Beetroot, and is, of course, liable to be transferred from one to the other. Hitherto no remedy has been discovered, and wherever it appears it would be advisable not to plant another crop of Potatos on the same soil until after the cultivation of some intermediate crop of a different character, and the soil has been disinfected from any trace of the fungus. For further notes see " Beetroot Tumour." Journ. B.H.S. xxvii. p. 1180 ; xxviii. 1904, p. 695 ; xxix. 1904, p. 143, fig. 29 ; Gard. Chron. Oct. 28, 1905, p. 308, figs. 120, 121 ; Nov. 11, 1905, p. 346. Potato Disease. Phytophthora infestans (De Bary), PI. IX. fig. 118. So many volumes have been written in connection with the Potato disease that little remains for us to say. Unfortunately, its ravages are too well known to need description, and a patent universal remedy we have not yet found. The mycelium of this rot mould is more slender than usual, and the fertile threads are also comparatively slender, being attenuated upwards. These threads are also sparingly branched in the upper portion, with a few slender tapering branches, which are either simple or sometimes divided. On the branches are scattered swollen processes, which corre- spond to the points of origin of the conidia. The latter are elliptical and colourless, with a prominent papilla or teat-like projection at the apex (25-30 + 15-20 h). The life-history of the rot moulds is given in the Introduction. The question of resting spores in this species must still be open to individual opinion upon the strength of the evidence afforded, to which we give references. To a certain extent spraying with Bordeaux Mixture has been of service. A damp situation is favourable to the disease, and so is a wet season. Sacc. Syll. vii. 802 ; Cooke, M. F. f. 264 ; Cooke, HdbJc. No. 1774 , Mass. PL Dis. 62, fig. 7; Mass. B. F. p. Ill, figs. 121-126; Grevillea, v. p. 18, pi. 70-73 ; Ward, Dis. p. 59 ; Gard. Chron. July 1875 ; Smith, Field Crops, 275; Ttibetcf, Dis. p. 119; Journ. P. U.S. xxviii. 1904, p. 600 ; xxix. 1904, p. 139. 94 FUNGOID PESTS OF CULTIVATED PLANTS. Potato Sclekote. Sclerotinia Sclerotiorwn (Mass.), PI. VII. fig. 119. Curious hard fungoid bodies, having the nature and functions of a resting mycelium, are sometimes found within the tissues of various plants. These are called " Sclerotia," one form of which is known as " Ergot." They vary much in size and appearance, but are commonly oval or oblong with a dark outer coat, and an interior of compact cells. Potato haulms, all the parts above ground, have been known to produce sclerotia in such numbers as to become a veritable pest. The whole plant becomes covered with a thick felt of white mycelium, within and without. The growth is very rapid, and ultimately numbers of small sclerotia are produced amid the felt, from the size of a pin's head to that of a bean. It was in 1883 that the ultimate development and destiny of these sclerotia were discovered. When the sclerotia are placed in a favourable situation after a period of rest, they commence to germinate. In this case it was a small fungus called a Peziza which was produced. There was a cuplike or saucer- like head, from a quarter to half an inch in diameter, proceeding from a long slender flexuous stem, about two inches long, arising out of the sclerotium. The inside of the cup is the fertile portion, and here long cylindrical cells are closely packed side by side, each one enclosing eight spores or sporidia, which are ejected when mature. The cup or Peziza was called at first Peziza postuma, but has since acquired the name of Sclerotinia. Fungicides are not likely to be of service, unless the disease is taken in a very early stage, but the precaution should be taken of burning up the diseased haulms to prevent the development of Peziza and spread of the germs. Gard. Chron. Sept. 15, 1883; Mass. PI. Dis. 150, fig. 32; Tubcuf, 1 1 . 268 ; Smith, Field Crops, 25, fig. 3 &c. Potato Rhizoctonia. A serious Potato disease is announced in North America, caused by Ehizoctonia Solani (Euhn). It was first observed in Long Island in 1900, and afterwards in Colorado, and is increasing in extent, so that growers in Europe must be upon their guard. It is reported that large sines gave promise of an abundant yield, but when digging time comes it is found that so few tubers have set that it does not pay to dig them. Many vines do not produce a single tuber. Il is by no means an uncommon occurrence for the vines to set an abnormal number of small Potatos, or "little Potatos " as they are f-all« d. These often occur in compact clusters, and are so small as to be worthless. Another condition is the dying of Potato plants, all of which conditions may be produced by attacks of Rhizoctonia. The hyphse of the fungus are often found on the surface and in the scab ulcers of Potato , These hyphse give rise to irregularly shaped dark masses known as sclerotia, which vary in size from that of a mere speck. to half an inch or more in diameter. These sclerotia resemble PL. VIII. PESTS— GARDEN VEGETABLES. FUNGOID PESTS OF CULTIVATED PLANTS. 95 small bits of earth, but by placing the Potatos in water these bodies become black and quite conspicuous. Many of them adhere very firmly. The hyphae spread through the soil in various directions ; hence a single diseased Potato may be the means of infecting an area of considerable size. Plants which are attacked when young, if not killed outright, are often dwarfed and frequently die long before tbe close of the season. The parts below ground are thoroughly infected with the Bkizoctonia. In some cases the disease attacks the plant just below the surface of the ground, and under favourable conditions a stem rot called " Collar Rot" or "Black Eing " is produced. When the attacks on the stem are not so severe as to cause death the injuries may prevent the assimilated food from being stored in the subterranean portion of the plant, large tops are produced, and green tubers often form in the axils of the leaves (see also Journ. B.H.S. xxvii. p. 1182 ; xxviii. 1904, p. 695 ; xxix. 1905, p. 870). Potato Bacteriosis. This has been described as occurring in Germany under the name of Bacillus pliytophthorus, App. Dent. Botan. Gescl. 1902, p. 128; Journ. B.H.S. xxvii., p. 1181; xxix. 1904, p. 145. We do not apprehend any danger to Potatos from the fungus described under the name of Phycomyces splendens, for surely it can only be a veritable saprophyte (see Garcl. Chron. June 26, 1886, p. 824). Potato Spot Mould. There has been some consternation in Europe upon the appear- ance of a black mould (Cercospora concors) on living Potato leaves, but it has not been heard of in Britain. Potato Macrospokium, or Leaf Curl. Two species of Macrosporlum have been described as affecting the leaves of plants of the Potato family, but one of these is decidedly a saprophyte and only occurs on dead leaves. The other (Macrosporium Cookei) attacks the living leaves of Potato in this country, and of Lycopersicum esculent um (Solatium Lycopcrsicum), in America, and has large conidia (60-70 + 10 /<) with from four to six transverse septa. The latter is not yet recorded as occurring in Europe. (Garcl. Chron. Sept. 23, 1905, p. 230.) Tomato Leaf Mould. Cladosporium fulvum (Cooke), PL VIII. fig. 120. This mould first made its appearance on leaves of the Tomato in the United States, and was described in 1883 from specimens received from South Carolina, since which time it has not only spread in America, but made its appearance in England, where it was first recorded in 1887. Brown felted spots of irregular size appear on the under surface of 96 FUNGOID PESTS OF CULTIVATED PLANTS. the leaves, as the first indication of this disease. The spots gradually spread, and the corresponding upper surface acquires a yellow colour. It sometimes extends also to the fruit. On the leaves the spots soon darken, and the leaves shrivel and dry. The mycelium consists of delicate colourless septate threads, which penetrate the tissue in all directions, and sometimes overrun the entire surface. From this mycelium arise erect fertile threads, which form dense tufts, simple or shortly branched, pointed and flexuous, with the joints swollen, and of a tawny colour. The conidia are produced at the tips of the threads, mostly elliptical, with one division in the centre, and pale brown (10-18 x 4-7 /x). Conidia may also be produced from the nodules or short branches and are sometimes met with in short chains of two to four attached end to end. They germinate readily in water by sending out germ tubes, which become interlaced in a mycelium. Spores placed on wounded fruit will produce rot. Two or three large cultivators have assured us that they have no difficulty with this mould so long as they control temperature and ventilation. Solution of sulphuret of potassium has been recommended for spraying. Saec. Syll. iv. 1731 ; Mass. PL Dis. 311, 435, fig. 83 ; Garcl. Chron. Oct. 29, 1887 ; U.S.A. Rep. 1888, p. 347, pi. iv. ; Joum. R.H.S. xxvi. 1902, p. 733, fig. 307 ; xxviii. pp. 142, 302. Tomato Black Rot. Macrosporivm Tomato (Cooke), PI. VIII. fig. 121. This rot was also first observed in the United States before it became known in this country. It makes its appearance at the apex, or flower end of the fruit, when the latter is from half to two thirds grown. At first a small blackish spot is seen, either around the remains of the style, or on one side of it. This rapidly increases in size, but retains a more or less circular outline. As the disease progresses the tissues collapse quite regularly on all sides, and the berry becomes much flattened. There is usually a slightly raised narrow border surrounding the diseased pails, while just outside this the cuticle retains its normal healthy colour, but appears slightly wrinkled owing to the collapsed con- dition of the tissues beneath. Sections show that the black discolorations extend deeply into the tissues. The principal cause of this disease is the black mould Macrosporium, the mycelium of which consists of rather large septate, thick-walled, and contorted threads, at first colourless, but eventually tinged with brown. permeating all the diseased and decaying parts, and easily traced into thr Bound tissue. Arising from the mycelium are the olive-brown fertile threads, of variable Length, which bear the large compound spores or conidia. The latter are obclavate, attenuated above, and shortly stalked below, divided transver ely and longitudinally into as many as fifteen almost cubical cells, after the manner of bricks in a wall, at first olive- brown, becoming almost black (100-120 x 20 22 (i). All diseased fruit and the old stalks and leaves should be burnt. Suggestions have been made for spraying with sulphuret of potassium. FUNGOID PESTS OF CULTIVATED PLANTS. 97 Sacc. Syll. iv. 2552 ; Grcvillea, xii. 32 ; U.S.A. Bcp. Agri. 1888, p. 339, pi. iii., iv. ; Mass. PL Dis. 324, fig. 89. Tomato Leaf-spot. Septoria Lycopersici (Speg.). This leaf-spot is known in the United States and in New South Wales, and recently has occurred in France. It was first discovered in Argentina, but has since become widely diffused. Sporuless 70-110 /i long, septate. Sacc. Syll. iii. 2904 ; Agric. Gaz. N.S.W. 13, 1902 ; Bull. Soc. Myc. de Fr. xxi. fasc. 3, p. 171, fig. 2. Tomato Bacteriosis. A bacterial disease of Tomatos has been destructive on the Continent, and since appeared in England. The fruit blackens and is at length wholly destroyed. Another similar disease, if not the same one, has made its appearance in the United States, where it attacks the Tomato, Egg Plant, Potato, and species of Petunia. The disease causes the foliage to wilt, and, later on, the stem and branches become discoloured and die. In Potatos the disease passes down to the tubers, causing a brown or black rot. Possibly this may be the same as Bacillus pkytophthorus. Mass. PL Dis. 338, 342. Sleeping Disease of Tomatos. Fusarium Lycopersici (Sacc). This disease has been prevalent in Guernsey, and in other places in Britain. The leaves become dull and droop, and the stem collapses. The root is attacked first, gradually extending to the lower part of the stem. Shortly after the sleeping stage, the portion of the stem above ground is covered with a delicate white mould, of erect branched threads, which produce small two-celled conidia (Diplocladiuvi). Afterwards, from the same mycelium, the spindle-shaped spores {Fusarium) are produced in immense numbers. Spraying appears to do no good. Gard. Chron. June 8, 1895 ; Journ. B.H.S. xix. 1895, p. 20, figs. 1, 2, 3 ; xxviii. p. 301 ; Mass. PL Dis. 328. Other Tomato Fungi. After the attacks of Macrosporium, and sometimes meanwhile, the spindle mould (Fusarium Sdani) will attack Tomatos as freely as Potatos, and complete the round of destruction. The Potato rot mould (Phytophthora infestans) will sometimes attack the Tomato, but must be well guarded against, as it would be a fatal foe if once it came to be established. Cultivators have been terrified by a long list of supposed Tomato diseases which has been thrust forward without any justification, except to alarm them. The majority of these are saprophytes, and only flourish at the expense of otherwise decaying vegetable matter. Such, for instance, are Sporocybe Lycopersici and Dactylium Lycopersici, which has a strong family likeness to Tricothccium roseum, and probably Phoma destriuliva 98 FUNGOID PESTS OF CULTIVATED PLANTS. and Sphceroncma Lycopersici. The latter has been renamed Glceospovium phlomoidcs. Doubtless they will all prove harmless enough for any other purpose than to allow the writer a remote chance of becoming immortal by means of strings of useless names. No fungicides will be required. Mint Rust. Puee in ia Mentha (Pers.), PI. VIII. fig. 122. All kinds of Mints are liable to infection from the common Mint rust which is plentiful on wild Mints : in gardens mostly when in damp situations. There is very little indication on the upper surface of the leaves, but the under surface is either sprinkled or closely beset with the roundish pustules, both of the uredospores and teleutospores, usually in company, the latter darker than the former, but both of them equally powdery. The cluster-cups are rare. The uredospores are one-celled, roundish, and of a cinnamon-brown, the surface studded with minute spines (17-28 x 14-19 p.). The teleutospores are nearly black in the mass, oval, divided across the middle into two cells, with a slight constriction at the suture. The apex of the upper cell is furnished with a small papillary tubercle ; the lower cell is attached to a deciduous stem. The whole surface of the spore is covered with small warts (26-35 x 19-23 /<). Possibly should a patch of Mint become diseased, it would be well to try cutting it down to the ground and burn it, since it may prove that the disease has not extended to the roots, and the new growths may be free, especially if cut down before the teleutospores have matured and fallen to the ground. Common nearly throughout Europe, and in South Africa and North America. Saec. Syll. vii. 2180; Mass. PL Dis. 240; Cooke, M. F. p. 204, figs. 69, TO: Cooke, Hdbk. No. 1474; Plowr. Brit. Urccl. 157. Khubarb Cluster- cups. JEcidium rubellum (DC). Rhubarb Leaves in gardens are sometimes disfigured by the large patches of this parasite, although by no means commonly so. The same fungus is common on the leaves of various species of Dock, from which it may extend to Rhubarb. Jt is very handsome, as far as appearance goes, and forms large crim- son -pot--, nearly an inch in circumference, while in the centre of these spots the cluster-cups are crowded and densely packed together. The white edges of the cup are torn like a fringe, and the ascidiospores, which occupy the centre of the cup, are produced in chains in the interior, and are nearly globose and rough. No further development has been seen upon the Rhubarb leaves, since it is affirmed that both the Uredo and Puccinia axe developed upon another and quite a dill'erent species of plant, which in reality is one of the Grasses. But our disease now concerns only the Rhubarb leaves. FUNGOID PESTS OF CULTIVATED PLANTS. 99 Sacc. Syll. vii. 2204 ; Cooke, M. F. 194 ; Cooke, HdbJc. No. 1632. Diseases of Beetroot will be better treated in connection with Field Crops. Spinach Black Mould. Heterosporiwm variabile (Cooke), PL VIII. fig. 124. The fading leaves of Spinach are liable to be invaded by a species of black mould, similar to that which affects Carnations, which is by no means so harmless as black moulds often are. The threads of the mycelium take possession of the tissues, and the fertile threads finally burst through the cuticle of the leaves. Definite rounded or irregular spots of a paler yellowish colour first appear upon the still green leaves, caused by the mycelium of the fungus. Then the surface of the spots becomes dotted with blackish points indi- cating the threads of the fungus bursting through the cuticle. These threads are flexuous, slender, knotted at the points and growing in small tufts. Conidia are produced at the tips of the threads, simple at first, then with one, two, or three divisions or septa (20-50 x 7-10 ^u). The surface of the conidia is minutely rough with small spines. Threads and spores are of a pale olive colour. When fully matured the conidia germinate freely at each joint, pro- ducing a slender thread. Spraying with Bordeaux Mixture should be resorted to in order to prevent dissemination of fertile conidia. Sacc. Syll. iv. 2310 ; Grevillea, v. 123. Spinach Rot Mould. Peronospora effusa (Babh.), PL IX. fig. 125. The mould which attacks Spinach is of the same kind as that which attacks Potatos, parsnips, and other vegetables. The pest appears upon the living leaves in greyish, rather dense velvety patches, sometimes an inch in diameter, and sometimes spreading widely over the leaf. The mycelium is present in the leaf before the mould makes its appearance on the surface. The threads are produced in abundance, issuing through the stomates. The stem is undivided below, but in the upper portion it is divided in a forked manner, from two to six or seven times, the final branchlets being somewhat awl-shaped and arched. The ellipsoid conidia occur singly at the tips of the branchlets (22-30 x 10-23 /j.) with a dirty- white or slightly violet membrane. When mature thoy fall off readily. Resting spores are produced upon the mycelium within the tissues of the plant, and are variable in size, of a bright brown colour, which is irregularly furrowed and ribbed (25-88 /* diam.). Known in France, Belgium, Germany, Scandinavia, Finland, Austria, Italy, and the United States. SaccSylLvii. 854; Gard. Chron. Ap. 11, 1885, fig. 87; Cooke, M. F. f. 214; 215, Mass. PI. Dis. 79 ; Mass. B. F. 124 ; Berlese, Icon, slvii. ; Cooke, Hdbk. No. 1781. II -1 100 FUNGOID PESTS OF CULTIVATED PLANTS. Gourd Anthracnose. Glaosporium orbiculare (B.), PI. VIII. fig. 126, conidia. This disease appears in orbicular spots on ripe gourds, melons, Sec. The pustules are often run together and confluent, with a common pore or orifice. The conidia are small and oblong, tinged with pink (about 14 x Sh /*), and are expelled in thin tendrils. The genus to which this spacies belongs is almost universally destructive, and affects various plants. The disease which is caused by them is known throughout the United States by the name of Anthracnose. As to the specific differences between the two species recorded as Glceosporium orbiculare and Glc&osporiiim heticolor it is not of much practical importance, and some at least of American mycologists believe them to belong to the same species. Recorded in Portugal as well as in Britain. Every effort should be made to prevent the dispersion of the conidia of all species of Glaosporium, by spraying, and destruction of the affected parts. Sacc. Syll iii. 8759 ; Cooke, Hdhk. No. 1407 ; Berk. Ann. N. H. No. 106, t. vii. f. 6. Cucumber Anthracnose. Gl. Recently some important investigations have been made into the causes of a peculiar form of Melon disease which is not uncommon in the United States. We have grave doubts whether the same disease was not present in this country in 1890, attacking Gourds and other Cucurbitaceous plants. The attacked vines are said to have varied somewhat in their appearance, but generally there was a decay of the stem, in proximity to the root, and then the whole plant wilted and failed to grow. It is reported that an examination showed that the decomposing tissues were teeming with bacteria. Inoculation of healthy plants was made, and it was found that, with no other fungus present, the germs obtained were abundantly able to introduce a rapid decay into Cucumbers, Melons r and Squashes, Cucumbers being the favourite, and in them the decay was most rapid, running through a four-inch fruit in a single day. The next step was the application of these germs to healthy plants in the field. When the application was made near the end of a vine, the latter rotted away in from three to four days. Numerous other experiments were performed, and all nearly equally successful in demonstrating that the diseased virus may be communicated by inoculation to healthy vines. Joum. B.H.S. 1891, xxvi. p. 540 (' Cucumber Wilt '), xxvii. p. cxcii. 104 FUNGOID PESTS OF CULTIVATED PLANTS. Onion Scab. Pi rmicularia circinans (B), PL VIII. fig. 131. During some seasons this disease is abundant, while in others it is scarcely known. It attacks the outer coating of the bulbs of Onions, and does them very little injury so long as they are in the ground. It usually appears when the bulbs are nearly full grown, under the form of scattered black patches formed of small black velvety tufts, and these are arranged in concentric circles or in irregular wavy lines. These tufts consist of quantities of erect threads, each bearing a long slender slightly curved and colourless conidium or spore at its tip. Besides which, the tuft is thickly studded with long black projecting spines winch gives it the velvety appearance. Has occurred in Germany and Italy as Avell as in Britain. The bulbs should be dry before storing, and none of the tainted ones should be mixed. When the diseased bulbs are separated they may be tried with a fungicide. Sacc. Syll. iii. 1376 ; Mass. PI. Dis. 273, fig. 71 ; Hard. Chron. 1851, p. 695, figs. ; Cooke, Hdbk. No. 1291. Onion Spindle Mould. Fusariella atro-vireus (Berk.), PL VIII. fig. 132. Berkeley has declared his opinion that the fungus above named is at least one of the causes of the mildew which is so destructive to Onions just before they arrive at perfection. The disease originates in little dot- like spots with radiating threads, crowned with a greyish gelatinous mass ; these at length unite, and the whole of the centre is occupied by the spores ; the border keeps on increasing, and often quite fleecy, especially if it meets with any impediment, but at length the whole mass is greenish-black, and the border becomes obliterated. The threads of the mycelium are white, and the spores are fusiform and curved, so as to form about one third of a circle. There is one peculiarity in moulds of this kind : that the spores seem to be held together for some time in a gelatinous heap, and do not separate until they are quite mature, and ready for diffusion. This peculiarity is rather an advantage, as it serves to localise fche attacks. Whatever fungicide is employed is of little import, so long as it will destroy the parasite without injury to the Onion, and it is likely to prove beneficial. Very little has been known of this disease for many years. Sacc. Syll iv. 187G ; Cooke, Hdbk. No. 18GG. Onion Rust. Pi'.ahiia Porri (Sow.), PI. VIII. fig. 133. Occasionally, for many years, this rust has attacked plants of the Onion tribe and caused great trouble. In 1883 a crop of Chives was attacked FUNGOID PESTS OF CULTIVATED PLANTS. 105 at Shrewsbury and almost destroyed by its ravages. A public trial took place in Edinburgh where damage was sustained to a crop through this cause. At other times a limited number of plants have sustained injury in gardens. There are declared to be, as usual, three stages in the history of this pest. First, the cluster-cups or JEcidium form, which is by no means trouble- some ; and then the Uredo form, which occurs in small reddish-brown pustules either scattered over the leaves or collected in clusters. The uredospores are either nearly globose or elliptically so, very delicately spinulose (20-33 x 18-27 /j), of a pale orange colour. The teleutospores are contained in flattened pustules of a darker colour, and are commonly of two kinds : one form is obovate and without any septa or division (25-36 x 15-23 /u) and the others are club-shaped, and divided into two cells (28-45 x 20-26 /j), of a chestnut-brown colour, and externally smooth, with a long slender pedicel. For this reason probably, this species has sometimes been called Puccinia mixta. Possibly other rust will sometimes attack cultivated Onions, of which we are said to possess three species. This is known, at any rate, in France, Germany, Finland, and Italy. Sacc. Syll. vii. 2155 ; Garcl. Chron. Oct. 15, 1891 ; Ploivr. Brit. Ured. 148 ; Smith, Field Crops, p. 39. Onion Rot Mould. Peronospora Schleidcni (Unger), PI. VIII. fig. 134. Of all the destructive rot moulds scarce one is more destructive, or its attacks to be more deplored, than the present : which will fall upon a crop of young Onions and destroy them in an incredibly short space of time. The mould forms broadly effused patches of greyish-lilac tufts, which sometimes entirely cover the leaves, so that in its early history it was known as Botrytis destructor. The fertile threads arise from the mycelium in tufts, and are large and without septa or divisions. The upper portion is branched alter- nately, or in a forked manner, and is again and again divided until the final branchlets are strongly arched. The conidia are obovate or egg- shaped, with the apex obtuse, or a little acute, and of a pale dingy-violet (45-55 x 22-25 /u). The resting spores are produced on the mycelium as usual, and are broadly elliptical or globose, with a comparatively thin and smooth coating. This is known in France, Belgium, Germany, Scandinavia, and North America. It is recommended as a good plan to sow the Onions in the autumn, so that they are able to make a good growth before the appearance of the mould in the spring. Berk. Ann. Nat. Hist. vi. p. 436, t. 18, f. 23; Sacc. Syll. vi. 857; Cooke, Hdbk. No. 1787 ; Cooke, M. F. fig. 263 ; Mass. B. F. p. 125 ; Berlese, Icon. xxv. ; Mass. PL Bis. 76 ; Smith, Field Crops, 45. 106 FUNGOID PESTS OF CULTIVATED PLANTS. Onion Sclerotk. Sclerotinia bulborum (Wakk.), PI. IX. fig. 135. This pest is liable to infest the bulbs of Hyacinths, Onions, and perhaps other bulbs, and destroy a great number. Yellowish blotches appear on the foliage in spring or early summer. These spots are soon covered with an olive-brown mould. The mycelium passes down into the bulb, and there blackish sclerotia are formed, from the size of a Mustard seed to that of a Pea, within the scales of the bulb, and sometimes covering the surface. During the following spring the sclerotia germinate and produce the Peziza or Sclerotinia, the sporidia of which are binucleate (16 x 8//). It is recommended that the diseased bulbs should be burnt to diminish the chances of dissemination from the germinating sclerotia. The further measures recommended arc spraying with Bordeaux Mixture diluted on the first appearance of the disease, or else the potassium sulphide solu- tion. The brownish tufts of mould are compact, the tips of the fertile branches spinulose, each spine bearing its conidium (9-10 x 7 /.<). Known hitherto in Germany. See also p. 69. Gard. Chron. xvi. 1894, p. 160, fig. 25 ; Mass. PL Bis. pp. 157, 380 ; Sacc. Syll. viii. No. , ascus with sporidia ; e, young ascus; f, paraphyses. PESTS OF ORCHARD AND FRUIT GARDEN. Fruit-growers will find indicated in the following pages most of the pests which are likely to trouble them in their occupation. The arrangement is rather an artificial one, but it appeared to be best suited to the wants of practical men. Orchard trees will occupy the first portion, whilst the latter will be assigned to bushy and herbaceous plants with marketable fruits. Anomalies may be sometimes anticipated, as, for instance, placing Melons with Gourds and Cucumbers in the kitchen garden, and Tomatos in juxtaposition with Fotatos. The Grape Vine and Pineapple, and similar tropical fruits, will have to be dealt with by themselves. 110 FUNGOID PESTS OF CULTIVATED PLANTS. Apple-leaf Spot. Sep'toria pyricola (Desm.), PL X. fig. 1. Spotted leaves are common enough in the orchard and elsewhere, but they may have many causes, known and unknown, and cannot all be attributed either to insects or fungi. In most cases the spots on the leaves, although destructive to the leaf, unless very prevalent do not affect materially the general condition of the tree or the production of fruit, except in a few instances of a virulent kind. In the present instance the spots occur on the upper surface of the leaves of Apple or Pear, and are of a greyish-white with a narrow brown margin. They are commonly somewhat rounded, from a quarter of an inch in diameter. The substance within the spot is killed by the mycelium and bleached, with the surface sprinkled or dotted with little black points not larger than the prick of a pin. Each of these points consists of a small nearly globose receptacle with a minute pore at the apex which encloses the fruit, or spores, of the fungus. When fully mature these minute sporules ooze out at the orifice in the form of a tendril and spread over the surface of the leaf. The sporules in the present species are elongated and threadlike, with about two transverse divisions (60 x 3^ /.i) of a very pale olive tint. Found generally throughout Europe. Sacc. Sytt. iii. 2624 ; Cooke Hdbk. No. 1320 ; Seem. Jo urn. iv. f. 27. A large leaf-spot (Phyllosticta Pyrorum) is known in the United States, with much smaller sporules (10 x 2 /<). Apple-leaf Black Mould. Coniothecium Questieri (Desm.). This mould was first discovered in France nearly half a century ago on leaves of Coruus, and appeared in 1 ( J02 on fading leaves of Apple, although we have grave doubts of its being any other than a saprophyte. It occurs on the under surface of completely dead spots of i he leaves, or on thoroughly dead and brittle leaves. The tufts are ill and scattered in little black dots over the dead parts, but do not occur upon the merely discoloured and fading leaves. The conidia are conglomerated in variously shaped clusters of from two to eight cells (about 10 // diam.), of a pale brownish colour, mixed with occasional slender threads. Sacc. Syll. iv. 24 12 ; Tram. Br. Myc. Soc. (1903), p. 15. Apple-tree White Mould. Oidium fa/rinomm (Cooke), PL X. fig. 2. This mould whs first observed in 1870 and 1H71 covering the young twigs and Leaves of Apple trees with a mealy coating of white mould, so that they looked as if dusted with Hour or powdered chalk. Since the above it has become sufficiently common. Although it is a true epiphyte, it is capable of inflicting injury, causing the young leaves to curl, checking their growth, and distorting the tender twigs. FUNGOID PESTS OF CULTIVATED PLANTS. Ill There is a thin and delicate but profuse mycelium from which arise the fertile branches, which are club-shaped and divided by transverse septa into short joints, which gradually contract at the suture, and then the top joint having acquired an elliptical form falls away as a conidium, to be followed successively by the other joints, so that a continuous crop of mature conidia is ensured. They are externally quite smooth and colourless (28-30 x 12 p). The habit and structure of this mould are quite similar to the Oidium of the vine, that which precedes the Rose mildew, and the development of the different species of Erysiphe. In 1890 this mould made its appearance on Apple trees in South Africa, and possibly it is the same species as one which is common east of the Mississippi in the United States. In such cases dusting with dry sulphur is likely to be the most effectual treatment. In America the application of the ammoniacal solution of carbonate of copper is recommended. Grevillea, xvi. 10. Apple-twig White Mildew. Sphcerotheca Mali (Duby). A century ago one of the fungi closely allied to that of the Rose and the Hop was imperfectly described in France under the name of Erysiphe Mall, but very recently it has been revived by Dr. Magnus, who has seen and figured one of the conceptacles. It was said to be broadly effused ; the thin arachnoid threads of the mycelium interwoven ; the conceptacles rare, and scattered, subglobose, rugulose, and black. The mould already described here under the name of Oidium farinosum appears to be the mycelium and conidia of the above fungus, but at present the more perfect and complete condition with the con- ceptacles has not been met with in this country. In this instance we appear to have a " perennial mycelium in the host-plant, which grows along with the shoot each season, stunting its growth and eventually killing the tree." (Fig. 12.) Joum. R.H.S. (1902), xxvi. p. 737, fig. 310; Duby, Hot. Gall. 8G9. Fruit-tree Pustule. Eutypella Prunastri (Pers.). This compound Spho&ria is only parasitic in the e.irly st;ige, when spermogonia are evolved in tendrils through punctures of the bark. No one has seen the complete or true Eutypella stage, except on dead tissues. In this condition the perithecia are clustered together in definite pustules, some five or six, with long converging necks, which are sulcate or grooved at the extremity or ostiolum. The fructification is contained within the perithecia, consisting of eight sporidia, enclosed within a transparent ascus, of which there are several. The sporidia are cylindrical, curved, and but slightly 'coloured (6-8 x \\ fi). The spermogonia, which are developed earlier, ooze oui in tendrils from the mouths of the receptacles, and are known in thi under the name of Cytospora rubescens : they are not more than half the length 112 Fl'NGOID PESTS OF CULTIVATED PLANTS. . i ' i a t Fig. L2.- Apple Mildew [Spheerotlieca Mali). As the mycelium of the fungus appears to be perennial in the ti lies, diseased shoots should be removed along the line marked 1. Spraying does not check this disease. The point affected should be all cut away. FUNGOID PESTS OF CULTIVATED PLANTS. 113 of the conidia. It is reported that this is a wound parasite, and enters the stem through wounds made by pruning, finally causing discoloration in the centre of the stem (see figs. 13 and 11). The trees will continue to grow for several years after infection. Destructive to Apple and other fruit trees, especially Plum and Cherry. Sacc. Syll. i. 566 ; Cooke Hdbk. No. 2160 ; Joum. R.H.S. (1902), xxvi. p. 712, fig. 313 ; Ibid, xxvii. pp. 691, 936, 1152 ; Gaul. Chron. 1902, p. 235, fig. 80 ; Berlcse Icon. iii. pi. 85. Brown Kot. Manilla fructigena (Pers.), PI. X. fig. 12. This rot is not confined to the Apple and Pear, but attacks most orchard fruits, especially the Cherry, to which we shall refer it later on. (See "Apricot Brown Kot.") Thihm. Pom. p. 22 ; Joum. R.H.S. (1902), p. 738, fig. 311. Fruit Spot. Scptorla Ralfsli (Berk.). About the year 1851 Berkeley described a small fungus which accompanied spotting on ripe Apples ; but it never seems to have been demonstrated that it was the cause of the spotting, and as nothing has transpired since which leads to the conclusion that it is really a fruit disease we can dismiss it with a brief notice. The appearance caused is that of black patches of an irregular form on the surface of ripe Apples. Over these patches are scattered the minute points, which indicate the receptacles of the fungus. The sporules are long and slender (30 /u long) with six minute nuclei. Pears as well as Apples are said to have suffered from the same infliction. Sacc. Syll. iii. 3028; Cooke Hdbk. No. 1307; Berk. Ann. N. II. No. 715, t. xv. f. 6 ; Thiim. Pom. p. 122. Apple Scab. Fusldadlum dendriticwn (Wallr.), PI. X. fig. 3. This disease appears under different forms, but in all cases it seems to be caused by the same fungus. On the leaves it comes in small olive spots, which are somewhat rounded and gradually enlarge, and become velvety and irregular ; frequently two or three spots will run together and form a large irregular blotch. The mould also appears on the petioles and the young twigs. The threads of which the mould is com- posed have a radiating habit, from which its specific name is derived. On the fruit its appearance is similar, but as the spots increase in size the cuticle cracks and forms a light-coloured ring about their margin. The greatest vigour is towards the edge of the spots, where the fruit seems stimulated to the production of a kind of corky layer in its efforts to throw off the disease and the formation of scab. Generally the result is to produce on the fruit crackings with a thickened scabby edge. The mycelium is rather superficial, and produces short erect brown threads at the apex of which the spores, or conidia, are produced. These I Ill FUNGOID PESTS OF CULTIVATED PLANTS. I'ki. I:;. Hi iyiki.i.a PitcNAsTlU. FUNGOID PESTS OF CULTIVATED PLANTS. 115 bodies are somewhat oval, attenuated towards each end, so as to be tbickest in the middle, or they are of an elongated pear- shape, and coloured brown, like the threads, but varying much in form and size. Although usually consisting of only a single cell, the conidia are sometimes divided bv a septum towards one end into two unequal cells (30 x 7-9 fi). The conidia germinate rapidly in water or moist air, and scab spots on the fruit may be found covered with vast numbers of germinating spores. The germ tubes are rather thick and coloured, with frequent divisions, or septa ; sometimes the germ tubes will produce secondary spores at their tips, wbicb in turn germinate like the original spore. The conidia will germinate in pure water (50° Fahr.) within eight hours. It is believed that the mycelium is perennial, living in the fallen lea vi- and twigs, and especially in the fruit, during the winter. It has been observed in America that the individual cells or joints of the mould, under favourable conditions, will push out germ tubes and develop new individuals of the species. " This method may be roughly compared to reproduction by root cuttings in higher plants." In early spring spray thoroughly with sulphate of iron. As soon as the fruit is set apply Bordeaux mixture or a modified preparation of eau celeste. In storing fruit especial care should be taken to separate all Apples which show any signs of " scab " from those which are sound and healthy, and store in a dry place. This pest is recognised in France, Belgium, Germany, Austria, Italy, North America, and Australia. Gard. Chron. Nov. 28, 1885, figs. 155, 156 ; Mass. PI. Dis. 302. fig. 80 ; Sacc. Syll. iv. 1612 ; Sacc. Fun. Ital. t. 782 ; Cooke Hdbk. No. 1747 ; U.S.A. Dep. Agri. 1887, p. 341, with figs. ; Thilm. Pom. p. 15 ; Gfrevillea, xx. p. 27 ; Tubeuf, Dis. 219, fig. ; Journ. B.H.S. xxviii. p. 292. Apple rot, after scab, causes serious trouble in the United States. It is attributed to the common mould, Ccphalothecium roseum, which has always been regarded as a saprophyte in Britain. {Journ. B.H.S. xxviii. p. 233 ; xxix. 1901, p. 91.) Bitter Rot of Apple. GlcEospormm fructigenum (Berk.), PI. X. fig. 4. Under the above name a disease is known in the United States which is attributed to this fungus as a cause. In this country it is rather doubtful whether the fungus is the cause of disease, since it has been affirmed that in most observed cases the fruits have been decayed before the fungus made its appearance. Still it must be conceded that nearly all the species of the genus to which it belongs are active parasite-. The pustules are circularly arranged in a cluster of a dirty rose colour, at length splitting the cuticle at the apex to discharge the contents. The conidia are cylindrical, sometimes curved, rounded at the ends and colourless (20-30 x 5-6 /<), produced at the tips of nearly equally long hyaline threads. Notwithstanding that the fruit exhibits decay with us before the fungus is detected it may prove to be true that such decay has been i 2 116 FUNGOID PESTS OF CULTIVATED PLANTS. V^tJCWf^CHNl 5 r r^ Fig. 14.— El-i vii i.i.\ Pbunastei, causing a Disease or Nobsery Stock. \ young Peach branch becoming shrivelled, indicating that the Btock is dying. (Natural size.) I!. The conidial stage of fruit bursting through the bark. (Natural size.) 0. The second or ascigerous condition of fruit, bowing at the surface through transverse cracks in the bark. (Natural size.) J). Shi lace of view of the second form of fruit, surrounded ''>' t'"' ruptured bark. ( 40.) E. Cruciate mouth of a perithecium. ( 100.) P. A: nis and spores. ( ■ 400.) G. Section through asoigerous form of fruit, (x wo.) II. Section through conidial form of fruit. ( -30.) I. Conidia. ( > 1,000.) FUNGOID PESTS OF CULTIVATED PLANTS. 117 caused by the Glceosporium. In America it is said that " the affected Apple at first shows one or more black, or usually brownish, spots on any part of the surface ; as these gradually enlarge their shape becomes more or less circular, and their borders somewhat sharply defined, sometimes the spots coalesce, or run together, and in this manner the entire Apple is soon affected. Towards the centre of the diseased spot there is usually a very dark, frequently almost black, discoloration. The darker portions are studded with minute black points, which are slighly raised above the surrounding tissue, imparting to their surfaces a somewhat roughened appearance ; occasionally these points are arranged in circles or grouped in little clusters." It is affirmed that the spores when sown in water germinate within ten hours by sending out one or more thickish germ tubes. In about twenty hours they will produce at their extremity globose bodies (8 (j. diam.), more or less dark-coloured, which are of the nature of secondary spores. These secondary spores germinate in like manner, and produce, in a third series, the same kind of bodies as the original primary conidia. So that by an alternation of generations the old type is reverted to. In addition to the above it has been announced that thick-walled cavities have been found at the base of the conidia-pustules, which con- tain minute colourless bodies resembling spermatia ; what may be their purpose or destiny is still an open question. No wonder, then, that the Apple growers of the United States have been cautioned that they " have a dangerous foe to contend with," and they are on the alert. The fungus is known in Britain, Italy, and the United States. The remedies suggested are spraying with a solution of one half an ounce of sulphate of potassium to one gallon of water. Application at intervals of ten days. In some cases the disease was arrested after the first application. Another fungicide applied with success is the ammoniacal carbonate of copper solution. Grapes are also liable to the same disease. Sacc. Syll. iii. 3751 ; Mass. PL Dis. 281, fig. 75 ; Gard. Chron. 1856, p. 245 ; U.S.A. Dap. Agri. 1890, pi. iii. ; Cooke Hdbk. No. 1411 ; Thiim. Pom. 59; Tubeuf, Dis. 482; Journ. R.II.S. xxviii. 1901, p. G26 ; xxix. 1905, pp. 746, 755. Apple-tree Antheacnose. ( ' rb.eosporium Malicortis (Cord.). Under the name of dead spot or black spot this new disease has made its appearance in various parts of the United States and British Columbia. Branches two or three inches in diameter are usually attacked, and the disease appears first in the autumn. Journ. R.II.S. xxviii. p. 233 ; U.S.A. St. Bel. Montana Rep. 1902. Insecticides for Orchard and Bush Fruit, see Journ. R.II.S. xxix. p. 816. Apple Si-kck. Spilocaa Pond (Fr.). An enumeration of the fungi which attack Apples and Pears would not be complete without reference to two or three obscure species which 118 FUNGOID PESTS OF CULTIVATED PLANTS. are reported to have occurred on the fruits. The little black specks upon ripe Apples Avhich resemble fly-spots have not afforded any evidence of fructification. Known under the above name, they are probably only incipient conditions of " Apple scab." The Splicer la Malorum of Berkeley, found upon decaying Apples lying on the ground, would be Outside the bounds of our inquiry, since it is clearly a saprophyte, and possibly only Diplodia Malorum. In 1878 Baron von Thumen published a work entitled " Fungi Pomicoli," in which he enumerated thirty-one fungi as growing on Apple and twenty-three on Pear trees, or their fruit. It is consoling to find that the majority of these are in no respect parasitic, and many of them common to all kinds of vegetable matter. Hence it is no guide to orchard pests. Ft. Syst. JSIyc. iii. 501 ; Thilm. Pom. p. 9." Apple Brown Spot. Surface of the fruit and interior marked with brown spots. Cause unknown. Garcl. Chron. Sept. 9, 1905, p. 208. Apple-twig Tumour. Botryodiplodia pyrenophora (Sacc), PI. X. fig. 5. Little swellings are sometimes to be seen on Apple twigs in which the bark cracks in an irregular manner and exhibits beneath a cluster of black I'n.. 15 Si'ii.KKorsis Malorum. perithecia, about the size of pins' heads, closely packed together, and seated upon a kind of cushion formed from the mycelium. These perithecia when mature contain a mass of rather large elliptical sporules, at first one-celled and colourless, but afterwards divided across PL. X. PESTS— ORCHARD, &<= FUNGOID PESTS OF CULTIVATED PLANTS 119 the centre into two cells, and then of a deep brown colour. Possibly this is only a condition of a more highly organised fungus in which the spores are contained in asci. It seems rather doubtful whether the "chancre" attributed to S])]ueroj)sis Malorum (Bull, de la Soc. Myc. de France, 1903, p. 134) may not be a condition, or stage, in the development of this same disease. (Fig. 15.) At present this is a rare disease, and must be hunted after to be discovered ; but it is quite possible for it to become a pest if it establishes itself in an orchard. Hitherto we have no record of its having become troublesome, and consequently no experiments have been made for its eradication. We should certainly recommend its destruction wherever found, since it is quite capable of. extending itself both by its mycelium and sporules. Sacc. Syll. iii. 2121 ; Cooke Hdbk. No. 1254. There is a small twig pustule, caused by Phoma Mali, which is not so clustered or conspicuous on the twigs of Apple and Pear trees. The sporules (8 /x long) are expelled when mature, and in some places it is looked upon with suspicion. Apple-tree Ca.nker. Nectria ditissima (Tul.), PL X. fig. G. Ten or twelve ymi's since K. Goethe propounded the opinion that canker on Apple trees was produced by the growth of the above-named fungus, which is of the Spharia kind, a little resembling these clusters of red Nectria which are so common on Currant twigs, but smaller. Goethe claims to have demonstrated his position by cultivating the parasite both from conidia and ascospores. The same fungus he contends produces canker on various kinds of Pear trees, and the sporidia of the Nectria from the Apple were found to produce canker on the Beech and Sycamore, and again from these trees on the Apple. According to Hartig the fungus enters through wounds caused by hail or the puncture of an insect. The best remedy, according to these authorities, is to cut out the diseased tissues and anoint carefully with coal tar. The fungus consists of a number of little red dots, scarcely so large as a pin's head, growing in clusters in cracks of the bark. These minute dots are spherical and smooth, seated on a white mycelium, and when mature enclosing a kind of pulpy nucleus, like a tiny drop of gelatin, and which consists of a great number of long cylindrical tubes, or asci, each enclosing a row of eight elliptical sporidia, which are divided by a trans- verse septum into two cells. When ripe they are capable of germination from each cell (14 x5-6^x). Occurs in France and Germany. Gard. Chron. March 8 and April 19, 1884, p. 313 ; 1891, p. 300, figs. ■66, 67 ; Sacc. Syll. ii. 4671 ; Mass. PL Dis. 127, fig. 24 ; Grevillea, ix. p. 116 ; Tubeuf, Dis. p. 187, figs. 120 FUNGOID PESTS OF CULTIVATED PLANTS. Apple-bark Valsa. Valsa ambicns (Fr.), PI. X. fig. 7. It is only during the past year or two that we have become satisfied that this usually saprophytic fungus has seriously affected living Apple trees — at least during its early or conidial condition. The bark of living branches and trunks was observed to be roughened with little elevations from the apex of which proceeded what appeared to be a long twisted yellow filament, not thicker than a horse-hair, entangled together into a mass of golden threads. When moistened these threads dissolved into myriads of minute curved conidia (5 /.i long) which had oozed out from minute punctures of the bark, and proved to be those of a fungus called Cytospora carphosperma, common on many orchard trees, but heretofore considered saprophytic. The mature condition is to be found in spring on branches that have lain on the ground through the winter, and consists of clusters of receptacles, flask-shaped, with long converging necks, containing sporidia which are cylindrical, curved, and rounded at the ends (16-18 x 3-4 /j), and of these eight are produced together in a membranous sac or ascus. This mature condition is only arrived at after hibernation, and con- sequently upon dead branches, but the early stage is clearly parasitic and may become troublesome. The mature stage is called Valsa ambicns. Certainly whenever seen oozing out of living trees the parts should be well rinsed with Bordeaux mixture, so as to destroy all the germinating power of the conidia. Sacc. Syll. i. 512 ; Cooke Hdbh. No. 2475 ; Curr. Linn. Trans, xxii. t. 48, f. 138. Apple-tree Hydnum. Hydmim Schiedermayeri. Very recently this large fleshy fungus has been developed on an old Apple tree at Maldon, Essex, bursting through the bark in a long strip, extending for 3 or 4 feet in an irregular mass. It has a nodulose appearance, of an ochrey-yellow or flesh-colour. The nodules produce long spines, which are covered by the hymenium producing the spores. According to Thiimen, this fungus is very frequently destructive to Apple trees, and is presumably a wound-fungus, the spores entering through a wound or fissure of the bark, and soon becoming developed. Gard. Chron. Oct. 31, 1903, p. 299 ; Mass. PL Dis. fig. 39. Pear-leaf Cluster-cuts. Iimstelia cancellata (Reb.), PL X. fig. 8. There is hardly any parasite which appears to be such a puzzle to gardeners as the Boestelia or " cluster- cups " of the Pear leaves. They have also been a puzzle to others who are not gardeners, as evidenced by the literature of the past quarter of a century. We can permit the discussion to rest and state a few conclusions. The parasite thickens the Pear leaves at the infected spots by the internal growth of the mycelium upon this, and externally are produced FUNGOID PESTS OF CULTIVATED PLANTS. 121 a small cluster of flask-shaped pale brown bodies called peridia, and these are soon split lengthwise nearly to the base into thread-like filaments which are for a long time united together at the apex. The contents of these flask-shaped bodies are the aecidiospores, which are nearly globose and warted on the surface (25-40 x 18-25 m). These spores are produced in chains, readily separating from each other. Spots are also to be seen on the opposite side of the leaf to that which bears the Bcestelia and corresponding to it. These are conspicuous by their orange colour, which becomes reddish, sprinkled with blackish dots, which indicate cells containing very minute bodies called spermatid, which are expelled when mature. It is recorded in Hooker's "British Flora" that when young Pear trees are planted near old trees suffering from the Bcestelia the young Fig. 16. — Peak-leaf Clcster-cup. A fungus growing on two different kinds of plant at different periods of its life-cycle. The spring stage of the fungus on a living Juniper branch, reduced in size. 2. Spore of same, x 300. 3,4. " Cluster-cup," or summer form of fungus fruit on living Pear leaves, reduced in size. 5. Two cluster-cups, one cut open, slightly x . 6. Spores of cluster-cup condition, x 300. trees have been observed to become much injured by the fungus. Mr. Knight sowed Pear seeds in soil infested with Bcestelia, and the very youngest of the seedlings showed the disease. According to theory it is contended that this kind of cluster-cups must also have a condition analogous to the Uredo and Pucciuia forms. As this is not known to take place upon the Pear tree itself, it is inferred that it must take place upon some other plant. The plant selected as fulfilling the condition is the Savin, and it is contended that the cluster- cups of the Pear tree produces those gelatinous exudations on the stems of the Savin which are known under the name of Ctyirmosporangium. (Ersted originated this suggestion in 1865, when he intimated that he had learned that gardeners were of opinion that the Pear fungus was never seen except after the appearance of the fungus on Savin. Hence 122 FUNGOID PESTS OF CULTIVATED PLANTS. he set to work to prove by cultures that the Pear fungus would produce the Savin fungus by inoculation, and vice versa. (Fig. 1G.) Incidentally Stevenson records that the Savin fungus is found in Scotland, but that the other condition, the Pear-leaf fungus, is not a Scottish plant. The advice given to gardeners by the theorists is to destroy all Savin bushes, root and branch, if they would save their Pear trees. Berkeley, however, wrote: — "If picking the leaves off carefully and burning them will not do, we may feel secure that an onslaught against the poor Savin bushes will not avail us." Known in France, Germany, Switzerland, Austria, and North America. Sacc Syll. vii. 2608 ; Cooke M. F. 193, t. 2, f. 2021 ; Ploirr. Brit. Ured. p. 230; Mass. PL Dis. 257; Thilm. Pom. 73 ; Cooke Hdbk. No. 1597 ; Gard. Chroii. 1862, p. 689; Tubeuf, Dis. 399, fig. Pear-leap Blister. Exoascus bullatus (Tub), PI. X. fig. 9. The blister of Pear leaves is a disease which has long been known in this country, distorting the foliage in a similar manner to the "curl " on Peach leaves. The under surface of the leaves is occupied by the external manifesta- tions of the fungus, but the mycelium penetrates the leaf. The glaucous appearance of the hollows of the blisters consists of tufts of small cylindrical cells, or asci, each containing eight small ovate uncoloured sporidia (5 ^ diam.). When these sporidia are mature the asci are ruptured at the apex, and they escape. When first discovered this fungus was called Oidium bullatum, until the presence of asci was determined. " In many cases these blisters formed two parallel lines on either side of the midrib, but sometimes they were irregularly scattered over the leaf. In some cases the blistered part had become black, and in others the portion of the leaf which had protruded had fallen out, so as to leave a regularly defined aperture. The cavities were found to be lined with a thin white stratum, consisting of myriads of confluent white specks of a waxy rather than a powdery appearance." It is incumbent upon the cultivator to pick off all the blistered leaves and burn them, so as to keep a check on reproduction. Spraying young trees with Bordeaux mixture at intervals of a fortnight may be pre- ventive. Jowrn. It. U.S. ix. p. 48; Sacc. Syll. viii. 3313; Mass. PI. Dis. 90, fig. 18 ; Cooke Hdbk. No. 2232, fig. 842. Pear-leaf Blight. Entomosponum maculatum (Lev.), PI. X. fig. 10. This disease is very destructive in the nurseries of the United States, although its presence in this country is rather doubtful. Small red spots on the leaves first appear : these increase in size and become brown, or it may extend over the leaf, which then shrivels and falls to the ground. FUNGOID PESTS OF CULTIVATED PLANTS. 123 The conidia, or spornles, have a very peculiar form, consisting of two nearly equal uncoloured cells attached end to end, and two smaller cells on opposite sides at the point of attachment, so as to present an unequal cross-shaped body. These conidia are produced superficially, in consider- able numbers upon the leaves, extending also to the fruit (18-20 x 12 /a). It also attacks the leaves of the Quince. Pear fruits when attacked are liable to crack ; hence a common name for the disease is "cracker." Spraying with Bordeaux mixture holds the disease in check, using a very dilute solution. Dead leaves should be collected and burnt. Sacc. Syll. hi. 3501; Mass. PL Dis. 276, fig. 73; Galloway, Rep. Agri. U.S.A. 1889, p. 357, pis. viii. ix. ; Tubenf, Dis. 480. Pear-leaf spots, as distinct from those on Apple, are also recorded as Plujllosticta pirina and Plujllosticta piricola in Southern Europe, Asco- chyta piricola in Italy, and Septuria nigerrima in Germany. Pear Scab. Fusicladiam pirinum (Lib.), PI. X. fig. 11. Between the Pear scab and the Apple scab there seems to be very little difference except in name. The conidia are the same in size, and the little difference in form can scarce be material. The external manifestations, both on the leaves and the fruit, are very similar : in the former case both form irregular velvety olive patches, which are apt to have a dendritic appearance on Apple leaves. The threads are short and rather robust, and the conidia are typically rather fusiform, being attenuated towards each end (28-30x7-9 jx), and we have never met them with a transverse division, whereas those of the Pear scab are usually of a club shape, and often divided into one large cell and one small one. Known in Germany, Austria, Italy, Portugal, and France. For remedies see also Apple Scab. Sacc. Syll. iv. 1643 ; Mass. PI. Dis. 304, fig. 81. A mould with fusiform conidia, not unlike Fusarium, is recorded as affecting ripening Pears in France. It has been named Discocolla pirina. Amkkican Pear Blight. Micrococcus amylovorus (Burr.), PL XI. fig. 25. Pear blight, or fire blight, is known only in North America, and was first observed in 1780, but no description of it until 1817. " It frequently destroys trees in the fullest apparent vigour and health in a few hours, turning the leaves suddenly brown, as if they had passed through a hot flame, and causing a morbid matter to exude from the pores of the bark of a black ferruginous appearance." The results of epidemics have been most disastrous, especially the memorable year of 1844. Various conjectures have been made as to its cause, the last of which, the bacterial, advocated by Professor Burrell, was supported by a long series of experiments by inoculating healthy branches with the juices of 124 FUNGOID PESTS OF CULTIVATED PLANTS. diseased ones and producing the disease, since which time the experi- ments have been confirmed. The organism named Micrococcus amylovorus consists of single cells, of oval or roundish shape (1-1} x \-\ /u) and quite colourless. For the most part they remain single, but may often be found in pairs, rarely a series of four or more, but never extending to chains. Sacc. Syll. viii. 3887; Amer. Nat. xvii. 1883, p. 319; Arthur, History and Biology of Pear Blight, 1886, plate; Grove, Syn. Bact. p. 10. Medlar Cluster-cups. JEcidium Mespili (DC). This species of cluster-cups appears now to be recognised as distinct and alone, without Credo or Puccinia to keep it company. It is only reported to occur on the leaves of Mespilus and Cotoneaster. Rounded or irregular spots are formed upon the leaves, which are yellowish or reddish on the upper side, with a yellow border, thickened in the centre. The cups are cylindrical, splitting at the edge into narrow teeth or threads. iEcidiospores angular (19 21 /x diam.), very minutely wirted and brown. There is a suspicion of this species having been found in Britain, but it evidently has never given any trouble as a pest. It occurs also in France and in Germany. Sacc. Syll. vii. 2773 ; Plowr. Brit. Ured. p. 232 ; Mass. PL Dis. 257. An anthracnose attacks the leaves of the Quince {Glccosporium Cydonice) in Southern Europe, as well as two or three kinds of leaf-spot, and Oidium Cydonice in Italy. Medlar White Mould. Oidium mespiUnum (Thiim.). This white mould occurs on the living leaves of Mespilus in Austria, forming broad white thin patches on the upper surface, which consists at first entirely of an epiphytal web of mycelium. From this shortly arise the fertile branches, which are at first simple and club-shaped. After- ward - two or three elliptical cells or conidia are cut off from the upper portion of the branches, and form the short chain of spores (10 x 6 /a) which ultimately acquire a pale grey colour. It is clear that this is an epiphyte of the same -character as the various species of Oidium which precede such mildews as that which attacks the Hop, Rose, Gooseberry, Maple, Garden Pea, and many other plants. In the case of any trouble the application of dry powdered sulphur is the safest remedy. Sacc. Syll. Lv. 208 ; Grevillea, xvi. 58. Another white mould (Ocularia necans) has damaged Quince and Medlar trees in Italy and France. Two kinds of leaf-spots are known on Medlar leaves, but neither is recorded as British. Phyllosticta Mespili and Scptoria Mespili are both of them European. Joum. B.II.S. xxviii. 1904, p. G98. M .c.C PESTS-ORCHARD. &>. FUNGOID TESTS OF CULTIVATED PLANT-. 125 Plum Powdery Mildew. Uncinula Prunastri (DC), PI. XI. fig. 17. This mildew resembles externally the previous species so much that it is scarcely possible to detect the difference by the naked eye. However, it is more commonly found on the wild Sloe than on the cultivated Plum. The mycelium is thin, and spreading over the surface of the leaves, giving them a frosty appearance, but never very dense. The conidia, in the early stage, are of the Oidium form, and are produced in short chains. The receptacles are globose and minute, scattered over the mycelium, and scarcely visible to the naked eye. The appendages which surround the base of the receptacles are very numerous and peculiar in their character, inasmuch as they are unbranched and curved at their tips in a hook-like manner, and are about twice as long as the diameter of the receptacle. Each receptacle contains from twelve to sixteen transparent pear-shaped sacs, or asci. each of which contains six sporidia. This species is found also in France, Belgium, Germany, and Italy. As an epiphyte, should this species threaten to give trouble, it should be met with the sulphur treatment. Sacc. Syll i. 23 ; Cooke M. F. 239. Plum Gummosis. Cladosporium epiphyllum (Link.). PL XI. fig. 18. Gumming, as exhibited in Prumts jaj . was made the subject of investigation by Massee in 1899, and the features were so apparently identical with those which takes place ordinarily in Plum and Cherry b - as to indicate the possibility of the cause being the same. Stout branches were mostly attacked, and the disease was indicated by tear-like drops of almost colourless gum oozing from the branches, drops increase in size so as to form irregular n - - as large as a Walnut. Soft in damp weather, but in dry shrinking and horny, they gradually change in colour from grey to black as they increase in size : but thi- a external, as the colour diminishes towards the centre. A black mould (Cladosporium epiphyllum) was traced as the cause of this disease, as a wound parasite, entering through small wounds in the bark, or where buds have been broken off. An olive patch of the mould first appears at the wounded point, and after the conidia are dispersed the drop of gum appears, and into this guru the threads of the mould extend. The threads are at first colourless and slender, but as the masses in the tips of the threads nearest the circumference become olive, and broken up into chains of cells, many of which produce small sclerotia or compact masses of cells with thick dark brown walls. If the mass remains damp at this stage myriads of very minute conidia are produced by the large brown cells. If the conditions remain unchanged the conidia increase rapidly by gemmation. When the mass is dissolved away to the ground the conidia continue to reproduce themselves by gemmation. Kew Bulletin, 1899, p. 1, pi.; Mass. PL Dis. 306; Sea. - '.". iv. 1718. 126 FUNGOID PESTS OF CULTIVATED PLANTS. Plum-tree Rust. Puccinia Pruni (Pers.), PI. XI. fig. 15. Nearly all kinds of Plum trees are subject to the ravages of the Plum- tree rust, but those attacks are not in all cases equally virulent. One tree may be seen in an orchard with hardly a leaf untouched, whilst another tree at twenty yards' distance will scarcely reveal a pustule. The under side of the leaves are generally closely sprinkled with the pustules, which split irregularly and discharge the spores, light brown or rusty-brown for the uredospores, dark brown for the teleutospores, in both cases powdery, and soon sprinkled over the leaf. The uredospores are egg-shaped or Pear-shaped, and the whole sur- face minutely spiny (20 35 x 12-16 /x). These are the ordinary uredo- spores, or, as we might call them, the true uredospores. In order to meet a difficulty certain authors have recently professed that two kinds of uredospores are known, the second and last invented kind being elongated and of a Uromyces type, so much so that it has acquired the name of Uromyces Amygdali. Whether this is also a Uredo form of Puccinia Pruni docs not interest us much, as we intend, in this place, to treat them as distinct diseases. The teleutospores are divided in the centre into two cells, each of which is nearly globose, except at their junction, where they are flattened, the lower cell being a little the smaller. The cell coat is chestnut-brown and thickly covered with rather rigid obtuse spines (30-45 x 17 25 /<). At first the short uncoloured pedicels are distinct, but these finally dis- appear. Known in Europe, North America, India, Cape Colony, Australia, and Tasmania. McAlpine I'm,,,. Bis. 23 ; Journ. B.H.S. xxvi. (1902), p. 963 ; Sacc. Syll. vii.; Plowr. Brit. Ured. 193 ; Mass. PL Bis. 251, fig. 64 ; Cooke Ihlhk. No. 1511 ; Cooke M.F. 211 ; Tubeuf, Dis. 355. Plum Pockets. Exoascvs Pruni (Fckh), PL XL fig. 13. Berkeley recognised this disease in LS70. The pockets, or "bladder Plums," appear soon after the fall of the flowers, attaining full sizeabout the end ^< Fig. 17. — Twig of Chebb? infksted with GnohoNXA BBTTHB08TOMA. 130 FUNGOID PESTS OF CULTIVATED PLANTS. fungus under the name of Coryneum Beijerinckii. Whatever may he the cause the remedy has not yet heen found. It is contended on hehalf of those who advocate the Coryneum theory that the disease may he communicated hy inoculation ; hut the presence of mycelium or even more advanced fungoid growth in the morbid spots is extremely probable, apart from any active participation in the disease. Unfortunately the disease is common enough, but the presumed fungus is so rare that only one or two persons have professed to have seen it in this country. It must be remembered also that the species of Coryneum otherwise known are saprophytes, and the presumption is strong against the assumed cause of gummosis. Massee contends that the cause of gummosis in Prunus japonica may be traced to the action of Cladosjiorium epiphyllum. It is recommended that diseased branches should be removed or collar pruning resorted to. The soil around the trees may be treated with quicklime on the surface to destroy conidia in the soil. Gard. Ghron. Mar. 29, 1881 ; 1891, fig. 68; Kew Bulletin, 1899, p. 1, plate ; Mass. PL Dis. 306, fig. 82 ; Mc Alpine Fung. Dis. p. 67. "Witches' Broom of Cherry. Exoascus Cerasi (Fckl.). Those peculiar malformations, which are known under the name of witches' brooms, are not uncommon on various trees, and amongst them the Cherry. Under these attacks the disease shows itself in the produc- tion of dense tufts of branches, growing apparently from a central point, and forming a bunch like a besom, which is very common on the Birch. This malformation is caused by the presence of a fungus similar to that which causes the leaf curl of the Peach, and which appears as a hoary bloom on the branches. The vesicles, or asci, which contain the sporidia are slender and club-shaped (30-50 x 7-10 /<), enclosing the nearly globose sporidia (6 9 x 5-7 /;). These asci are supported at the base upon a distinct stem-cell (10-16 x 5-8 or 3-5 /<), which is divided oft' from the ascus by a transverse septum. Known also in Germany, where it was first recognised and described. The only known remedy is to cut out the tufts and burn them. Sacc. Syll. x. 1731 ; Tubeuf, Vis. p. 163, figs. ; Mass. PL Dis. 89, 358. Cherry-leaf Scorch. Gnomonia erythrostoma (Ami.), PL XI. fig. 19. This disease sometimes makes it appearance in Cherry orchards in great numbers and proves destructive to the crop. The leaves arc attacked and soon present a scorched appearance, withering, but hanging on the tree through the winter. Long slender colourless curved conidia are produced, and in this condition it is known ;i - Septoria pattens. During the winter another and final stage is attained by the fungus produced on the dead hanging leaves {Gnomonia erythrostoma). In this lition the receptacles are immersed in the substance of the leaf, with FUNGOID PESTS OF CULTIVATED PLANTS. 131 a short beak, or ostiolum, which pierces the surface. Within the receptacle cylindrical cells, or asci, are produced, each of which contains eight elliptical sporidia, which are colourless and divided by a central septum into two cells (18 x 5-6 /<), each cell enclosing two guttules, and terminated by a curved hair-like appendage, which soon falls away. (Fig. 17.) Known in Germany, Switzerland, and Italy. All the dead hanging leaves should be collected and burnt. Frank says that in one district in Prussia this method was carried out for two seasons, after which the Cherry crop, which had been ruined, was restored. Sacc. Syll. iii. 2637, i. 2214 ; llass. PL Dis. p. iii. fig. 19 ; Jotirn. B.H.S. xxv. 1901, p. 313, fig. 162, xxvii. p. 1140 ; Tubeuf, Dis. 222. Shot-hole Fungus. Several species of leaf-spot have been recorded in Australia, and else- where, attacking leaves of Plum and Cherry, forming round spots, the dead tissue of which soon falls out and leaves a round hole in the leaf. American shot-hole fungus (Scptoria cerasina) occurs on Plum and Cherry leaves, and has strongly curved coniclia (50-75 // long). Another shot-hole fungus (Cylinclrosporiam Padi) having curved filiform conidia (18-62 x 2 /u) occurs also in the United States. An Australian shot-hole fungus (Phyllosticta prunicola) affects the leaves of Apple, Plum, and Cherry in similar manner in Italy, and extends to Australia (5x3 n). The genuine Australian shot-hole (Phyllosticta circumscissa), as it claims to be, attacks Cherry and Peach leaves (8 x 2 /u). Besides which a white mould (Ovularia circumscissa) is credited with forming similar shot-holes in Cherry leaves in Russia (15-18 x6-7/<)- And a black mould performs the same office (Cercospora circztmscissa) upon Plum leaves in the south of Europe, in the United States, and in Australia (50 x 3^-4 fi, 3-4 septate). Still another shot-hole fungus, and one of the most common in Australia, is a black mould (Glasterospor'mm carpophilum) on Peach, Almond, Cherry, and Apricot (54 x 14 n, 4-5 septate).- This is known also in Italy, Switzerland, Austria, and Portugal. Strange that none of these should yet have paid a visit to Britain. Mc Alpine Fung. Dis. p. 33. A shot-hole fungus has been found lately, ^several times affecting Peach leaves in this country, but not having seen it ourselves we are unable to determine the precise species of fungus implicated. A correspondent (Ganl. Gliron. Oct. 14, 1905, p. 282) states that he has used Campbell's Sulphur Vaporiser with good effect, but was not successful by spraying with Bordeaux mixture. Amehican Black Knot. Ploicrightia morbosa (Sacc). Although this is an American disease, unknown in Europe, it is the worst enemy of the Plum and Cherry in the United States. It forms black rough excrescences on the branches, often several inches in length. K 2 132 FUNGOID PESTS OF CULTIVATED PLANTS. At first the branch swells, which is followed by a longitudinal cracking and gaping of the bark. Then the surface is covered with a dark olive velvety coating of mould, which produces the conidia. Later on in the season the olive mould disappears, and a thick out- growth of fungus mycelium succeeds, which produces a stroma, or bed for the ensuing fungus. During the winter, cavities are formed in this stroma, and these contain cylindrical sacs, or asci, closely packed together, each enclosing eight sporidia, which are oblong, unequally two-celled (16-20 x 8-10 /i). As it is confined to the United States we must leave with the sufferers to adopt the best means at their disposal to exterminate the pest. Farloiv, Bull. Buss. Inst. 1876, p. 440, plates ; Sacc. Syll, ii. 5295 ; Mass. PI. Dis. p. 137, fig. 26. Cherry-tree Valsa. Valsa leucostoma (Fr.). Cherry-trees along the Elaine have shown signs of decay, the trees having suffered through late frosts exposing them to the attacks of a sphreriaceous fungus, long known as a saprophyte under the name of Valsa leucostoma. Cutting away the branches affected and putting tar over the wound has been effective. J own. B.II.S. xxviii. p. 242. Peach Rot, or Anthkacnose. Glceosporium Iceticolor (Berk.), PL XI. fig. 20. This disease attacks the mature fruits and produces depressed spots which are whitish in the centre with a blackened margin. The pustules are circularly arranged towards the centre, and are rosy, seated beneath the cuticle. The conidia, which are produced in the pustules, are oblong, with the contents retracted at each end, oozing out when mature in pale rosy tendrils (16-17 /* long). The same disease is credited with attacking Figs when approaching maturity, although some writers have suggested that the species which attacks Figs is the same as that which attacks Apples and Grapes (Olcjcosporium fructlgenum). The difference between them is mainly in the size of the conidia, whilst the precautions and remedies remain the same. All the species of " Anthracnose," as they are termed in America, are dreadfully injurious, and are recognised as the most persistent of pests. This is possibly the same species as ( 1 hrosporium fructlgenum. Sacc. Syll. iii. 3753 ; Gourd. Chron. 1859, p. 604, and December 6, 1890; Cooke Ihlbk. No. 1110; Thiim. Pom. p. 57. Peach Bust. Uromyces AmygdaU (Pass.), PI. XI. fig. 21. When the rust on the Peach leaves was first submitted to us wo declined to regard it as any form of Puce in ia Pruni, and accepted the name given by Passerini of Urumyces AmygdaU, Wo are concerned with PL. XII. 18 ©o\ PESTS-ORCHARD. &<= FUNGOID PESTS OF CULTIVATED PLANTS. 133 the rust of Peach leaves and not now with the usual form on the leaves of Plum, and it is our pleasure to treat them as distinct diseases. The underside of Peach leaves is liable to be affected with a rust the pustules of which are small and numerous. The cuticle is soon split, and the spores scattered as a fine rust-coloured dust. The form of these spores is quite unusual for those of a uredo, but approaching the type which is common in the teleutospores of Uromyces. They are consider- ably elongated, swollen in the middle, and almost bluntly lance-shaped, quite smooth externally, with the coat of the spore considerably thickened at the apex, and continued at the base into a rather short thick pedicel (35-40 x 12 p). In fact, more like the teleutospores of Uromyces than the uredospores of Puccinia. Latterly it has been suggested that these Uromyces spores are a third kind of spore, called " amphispore," constituting the cycle of Puccinia Pruni, several instances now being known in which uredospore, amphi- spore, and teleutospore are produced in succession. This rust is more common in the United States than it is with us but it is found also in Southern Europe and in Australia. Cooke in Bav. Fungi Exsicc. ; Cooke Hdbk. Austr. Fungi, No. 1734 ; see also Gard. Chron. Dec. 17, 1904, p. 418. Peach-leaf Blister. Exoascus deformans (Berk.), PI. XL fig. 23. Peach-leaf blister is such a common affection that a description is scarcely necessary. Sometimes aphides or other small creatures may produce somewhat similar appearances, but the real Peach blister is an established fact. The leaves are puffed up, blistered, and contorted in a variety of ways, and this disfigurement will proceed until it spreads gradually over the entire tree unless it is checked at once. The under surface of the leaves, in the hollows of the blisters, assumes a hoary or frosted appearance, and when examined under the microscope is found to consist of a number of cylindrical cells formed of a transparent membrane closely packed together side by side, each cell or ascus containing the elliptical sporidia (7 x 5 /j.) in the same manner as in the Pear blister and in the Plum pockets. This disease is sometimes called the " curl," from the curling and distortion of the leaves. Diseased or fallen leaves should be burned. Branches bearing diseased leaves should be pruned back beyond the point of infection. The disease is rampant if the leaves receive a sudden check from fall of temperature. Activity of the disease has been checked by a sudden increase of temperature. Known in France, Germany, Belgium, Sweden, Austria, Italy, North America, South Africa, Algeria, Australia, China, and Japan. Gard. Chron. July 9, 1887 ; Mass. PL Dis. 82, fig. 11 ; Cooke Hdbk. No. 2233 ; Berk. Outl, p. 376, t. i. f. 9, a. 6 ; Sacc. Syll. viii. 3341 ; McAlpine Fung. Dis. p. 13 ; Journ. Q.M.C. 1904, p. 58 ; Joum. B.H.S. xxix. p. 856 ; Gard. Chron. May 13, 1905, p. 294, fig. 121. 134 FUNGOID PESTS OF CULTIVATED PLANTS. Peach Freckle. Cladosporium carpoplrilum (Thum.). This disease is known in the United States as " scah " or "black spot," and was first observed in Austria in 1877, but has not been recog- nised anywhere else in Europe, although known in the United States and Canada and New South Wales, and is said to spread rapidly when once introduced. The fungus is a kind of black mould which attacks ripe Peaches, forming minute round spots or freckles, which are greenish, then brownish or olive. Finally the spots run together and form a brown crust, causing the fruit to crack, shrivel, and decay. It has also been observed on the foliage. The spots are orbicular, and the threads short and slightly branched or simple, with pale ovate conidia, which are rarely septate (20 x 5 fi). So nearly allied to the " Apple scab " that similar treatment is recommended. Sacc. Syll. iv. No. 1675 ; Mass. PL Dis. 310 ; Mc Alpine Fung. Dis. 49, pi. vii. Peach-spot Mould. Hclminthosporiiim rhabdifcrum (Berk.), PL XL fig. 21. This disease first attacked the Barrington Peach in 1861, but has never spread much since that time or proved of any great importance. Shallow pits, about half an inch in diameter, appear on the surface of the fruit the centre of which is occupied by a dark mould bearing a profusion of spores, so as to blacken the fingers when touched. The mycelium penetrates deeply into the fruit, which if not gathered in good time becomes useless. The mycelium consists of more or less waved articulated threads which give off here and there .stouter erect threads, with shorter joints, branched slightly above and producing at the tip of each joint a large spore. The spores, or conidia, are at first oblong and pale, showing one or two transverse septa. These rapidly acquire a dark tint, elongate, become more or less linear, and consist of from seven to eleven swollen divisions, of which the terminal one is mostly apiculate. Each division contains a few minute oil granules (50-80 /x long). After the spores have fallen they frequently split in the centre and give out a globular body, which is in all probability reproductive. We strongly suspect that this fungus is not a true parasite, but made its appearance subsequently, and was not the cause of disease. Gard. Chron. 1861, p. 938, fig. ; Cooke Hdbh. No. 1726. The "frosty mildew" caused by Cercosporella Pcrsicce has been known in America since 1890 on Peach leaves. Peach Yi.u.ows. This is one of the most mysterious of plant diseases, and although it has been known to occur in the United States for at least a century it has not found its way into Europe. In recent years " thousands of young and thrifty trees have been destroyed by it, and Peach growing has been FUNGOID PESTS OF CULTIVATED PLANTS. 135 abandoned in several parts of the country where formerly there were large and profitable orchards." The earliest symptom is the premature ripen- ing of the fruit ; then diseased dwarfed growths appear on the trunks and limbs. The limbs attacked are badly diseased»the second year, the entire growth being stunted and of a sickly green tinged with yellow. After this they may languish for a few years, and then die gradually from the extremities downwards. All efforts to discover fungoid mycelium has failed, and it is only recently that the disease has been attributed to microbes. In 1889 Professor Burrill intimated that he had found " in the tissues of the root and of the old and young stems of diseased trees an organism classed with the bacteria which is not known to occur else- where. This organism has been frequently obtained by method of cultures under circumstances which preclude the possibility of its coming from anything except the inner cells of the tree. He had it growing in artificial media, and it exhibited all the peculiarities of a pathogenic rather than a saprophytic microbe. He found it in every set of specimens which he examined, known to be affected by the disease, and has thoroughly tried in the same manner to find it in healthy stock and failed." Almond Twig Fusicoccum. Fusicoccum Amygdali (Del.). This disease has appeared in France, as pustules on living twigs of Almond-trees, breaking through the bark, and dispensing conidia 6 — 7^ x 23? — 3 p, allied to those of the common red Tubercularia. Bull. Soc. Myc. de. Fr. xxi. fasc. 3, p. 180, fig. 4. Silver Leaf. Stereum purpureum (Fries). This disease has been known as affecting fruit trees in this country for fully a quarter of a century, and has puzzled mycologists and pathologists to account for the cause. Recently Professor Percival has conducted some experiments which he considers will demonstrate that the disease is caused by a wound parasite, which in its fully developed form is a hymenomycetal fungus called Stereum purpurcum. At the same time it has been affirmed on good authority that several Horse Chestnut trees in Greenwich Park have been killed by attacks of this same fungus, which has, at any rate, been developed freely on the dead bark. Attacks Plum, Peach, and Apricot trees. We must still regard ourselves as sceptical as to whether the Stereum is the cause of "silver leaf," or the presence of too much nitrogen in the soil. Sacc. Syll. Hym. ii. 7284; Cooke Hdbk. No. 910; Joum. Linn. Soc., Bot. xxxv. p. 390, pi. x. 1902 ; Joum. B.H.S. xxvii. (1902), p. 712 ; xxviii. 1904, p. clxxiv ; Gard. Chron. Aug. 12, 1905, p. 111. Apricot Brown Rot. Monilia fructigena (Pers.), PI. X. fig. 12. This disease attacks indiscriminately a number of pulpy fruits, the Apple and Pear in this country, and the Cherry and Apricot in the 136 FUNGOID PESTS OF CULTIVATED PLANTS. United States. In 1864, which was a very dry season, the Apricots in many gardens were attacked. Fruits were in some cases spotted whilst quite green, in other cases the attack did not seem to take place till they ** / :! ••; ^ Fig. L8. Bbowk Boa of Fbum (Monilia fructigena). were nearly ripe. The intermediate or half-ripe condition was apparently that in which the attack was most prevalent. The first indication was a little discoloured brownish spot, very slightly sprinkled with whitish minute tufts of threads, on some of which a solitary spore might be FUNGOID PESTS OF CULTIVATED PLANTS. 137 found. The subjacent tissue at this stage is traversed by multitudes of thick, succulent, branched threads. The progress of the disease is rapid, the brown spot increases in size, the centre is occupied by a dense mass of mould consisting of closely set roundish tufts the threads of which bear necklaces of spores, the central ones lemon-shaped, and as the disease spreads the little tufts often assume a concentric disposition. At length the whole fruit gives way, and either drops off or remains attached to the tree, withered and wrinkled, like a large mouldy Plum (conidia 25 x 10-12 /,). (Fig. 18.) The methods hitherto recommended for this disease are to remove and destroy all diseased fruit and to spray the trees, so as to prevent the germination of all the spores which may be adhering to the bark. Dissolve four pounds of sulphate of iron in five or six gallons of water. Gard. Chron. Aug. 27, 1864 ; Mass. PL Dis. 300, fig. 79 ; Sacc. SylL iv. No. 157 ; Cooke Hdbk. No. 1812 ; Tubeuf, Dis. 497 ; Journ. R.H.S. 1902, xxvi. p. 738, fig. 311 ; McAlpine Fung. Dis. p. 53, pi. viii. fig. 2 ; Joum. Q.M.C. 1904, p. 61. Walnut Axthracnose. Marsonia Juglandis (Lib.), PI. XII. fig. 26. This parasite on Walnut leaves has long been known in this country, and certainly sometimes appears to take possession of nearly every leaf of a full-sized tree. The spots appear on the under surface of the leaves, and are large, often irregular in form, being limited by the veins of the leaves, generally of a greyish colour, at length causing the leaves to fall. The pustules are seated on the spots, and are flattened and of a brown colour, at length expelling the mature conidia through a pore or fissure. The conidia are somewhat spindle-shaped, a little beaked at the apex, and divided by a septum across the centre into two cells (20-25 x 5 /u). It has been recorded in France, Germany, Portugal, and Italy. Sacc. SylL iii. 4028 ; Cooke Hdbk. No. 1233. Fig Anthracnose. Glozosporium fructigenum (Berk.), PL X. fig. 4. In the year 1864 certain Fig orchards in Sussex were attacked by a disease, so that the whole crop became more or less affected, and the fruits dropped off before they were ripe. On this occasion the fungus appeared as a circular patch of little pustules, which were destitute of any common receptacle, but constituted little cavities which contained a mass of minute hyaline elliptical sporules, or conidia, enclosing a small nucleus at each extremity. When matured the walls of the cell con- tracted, and the sporules were forced out from an opening at the apex in the form of little tendrils. We have referred to this same disease previously as attacking Apples, and must revert to it for any additional information. Garcl. Chron. 1856, p. 245, Aug. 27, 1864 ; Mass. PL Dis. p. 281 ; Cooke Hdbk. No. 1411. 13fl ODD PESTS 01 CULTIVATED PLANTS. FlO-TBBE Canker. ■ I la ulccrata (Mass.). T})')< Is a disease which 1ms recently been recognised as causing id canker in the bark of Fig trees and shelling off large patches • fruit of the fungus is produced within minute cavities of the bark, imall conidis ooze out to the surface like fine hairs, winch ed of conidia stuck together by a tenacious gluten which i by moisture and liberates the exceedingly small conidia. These conidia obtain an entrance into the bark through wounds, and thus the disease is spread. imended that all wounded surfaces should be coated with tar at once. !'•;• no means should any knife be used in pruning or trimming which has been employed in cutting out diseased parts until it has been i I and disinfected, as a knife with adhering germs has known to infect a healthy tree. Gard. Mag. July 28, 1898, fig.; Mass. PI. Dis. 292. Fia Ci;kv Mould. Botrytis cinerea (Pers.). Only recently we hav< been made acquainted with the serious injury inflict* d oi Figs by the attacks of a grey mould, which it is difficult pecifically from Botrytis cinerea. The mould appears in v patches at the apex of the fruit, being preceded by a soften- and rotting appearance of the tissues, which are soon reduced to a pulpy mass. No trace ( .f sclerotia has yi t been observed. The sterile hyphee are creeping, interwoven; the fertile arc erect, in broad patches, of a greyish colour, either simple or sparingly branched, with several short simple or divided brancblets near the apex, constricted at the septa, smoky-brown (about 12-14 /< thick) ; conidia broadly elliptical or almost subglobose, nearly colourless il<» 1 1^ i' diam.), collected in somewhat globose heads. It is hopele - to dream of saving the fruit when once attacked, but all d fruits should be burn! at once to prevent diffusion of the conidia. Spraying uninjured fruit may save them from attack. Mass. PI. l>. ■ 880; Cooke Hdbk. No. L801. Mi mi bbi i.i . \ i Spot. /'/, . . I'l. Ml. fig. 28. Mulberry leav< i omethnee marked by rather large irregular spots or bleached ti lied with a definite border line of brown. The are pah-, either dirty white or tinged with ochre. "\.r the upper i of the Spots numerous black dots indicate tl U glob link into the substance of the Within tin pr< duced the elongated cylindrical conidia, or sporuleS, which are curved, rather ol • the ends, and divided 068 by th» a, or <- I by four guttules, or nuclei, entirely FUNGOID PESTS OF CULTIVATED PLANTS. 139 colourless, and at first growing from short sporophores, or pedicels (40-50 x 4 /*). First observed in this country at Clevedon, and since then has been found in several localities. At one time the theory was promulgated in France that this disease of the leaves was the cause of " muscardine," or silkworm disease, but for lack of evidence the theory soon gave way. Trees when once attacked continue to sutler year after year with increasing energy. Cold weather appears to check it, but in warm seasons it extends rapidly. The disease is known in France, Italy, Germany, Austria, and Russia. Sacc. Syll. iii. 3136 ; Grevillea, vi. p. 72, xiv. 104 ; Gard. Chron. Nov. 1877. Mulberry-leaf Blight. Cercospora moricola (Cooke), PL XII. fig. 29. Nearly at the same time that the Mulberry spot appeared in this country another disease was found affecting the leaves of the Mulberry tree both in this country and in the United States. It belongs to a genus of black moulds which are really very persistent in their attacks and very troublesome to the cultivator, but not likely to be of so much importance to us as to countries where the leaves are required in con- nection with the silkworm industry. The spots occur on both surfaces, and are orbicular, of a reddish- brown colour. Upon these spots are produced tufts, or bundles, of short olive threads, which burst through the cuticle and produce at the apex of each thread a long narrow spore, or conidium, which is three or four septate, and narrowed towards one end (70 x3 //). No experiments have been made to control this disease, as in its present development it cannot affect the production of fruit. Sacc. Syll. iv. 2281 ; Grevillea, xii. p. 30. Mulberry Black Mould. Clasterosporium parasiticus (Cooke), PL XII. fig. 30. When tbe Mulberry-leaf spot was first found in this country it was accompanied by another fungus of a very different character, which appeared to be parasitic upon the same spots. Nearly every spot had its centre blackened by some parasite, which it was ultimately found had no relation whatever to the original disease. This fungus consisted of cylindrical spore masses with a short stem and almost always obtuse apex divided by numerous septa, and con- stricted at the joints so as to be torulose, or with a beaded appearance ; of a clear brown colour when mature, and not unlike a caterpillar in miniature. We have inserted this visitant here, not because we retain any suspicion that it will prove to be a pest, but as a guide to its identification should it accompany the leaf-spot again, and in order to secure more definite assurance that it is only a saprophyte on the dead tissue of the spots. Grevillea, vi. p. 74, with fig. 140 FUNGOID PESTS OF CULTIVATED PLANTS. Hazel-leaf Mildew. Phyllactinia suffulta (Sacc). Filberts being cultivated to a considerable extent as a table fruit, the shrub will fall more naturally into position here than in the shrubbery. The name by which the mildew was known for very many years was Phyllactinia guttata, but it has since suffered in the lust for change. The under surface of the leaves is frequently covered with a delicate white mildew consisting of a creeping interwoven mycelium of thin threads with short erect branches bearing conidia. In the course of time the little dark globose receptacles make their appearance, scattered over the surface of the mildew. These little conceptacles are encircled by a ring of spine-like, pointed, divergent appendages with a swollen base, which stand around and guard the receptacles. Each receptacle encloses from four to twenty hyaline pouches, or asci, which contain the sporidia, of which there are usually two, sometimes three or four in each ascus (40-50 x 22-25 /<). This is one of the superficial fungi to which it is believed that the application of sulphur is beneficial, as in the case of the Hop mildew. Sacc. Syll. i. No. 13 ; Mass. PI. Dis. 98, 361, fig. 16 ; Cooke M. F. xi. figs. 219, 220; Cooke Ildbk. No. 1912 ; Tubcuf, Dis. 179, fig. Hazel-leaf Spot. Septoria Avellana (B. & Br.). This leaf-spot was recorded by Berkeley, but does not appear to be of y common occurrence. The receptacles arc found on the under surface of the dry and bleached parts of the leaves, but the sporules are rather anomalous in size and form for this kind of spot, since they are fusiform and curved (10 /< long). Tin jpecii has al o been observed in Italy. Orevillea, v. p. 56; Sacc. Syll. iii. 2717. Hazel deaf Blotch. Ghwmoniella Coryli (Batsoh). This fungus he Long been known on Eazel leaves, and has had its name changed a great many times. It occurs on the living leases in black Bhining raised patches on the under surface, resembling little drops of pitch. Bach clu ■ d • vend receptacles arranged in a circle and immersed in the black stroma, with Long projecting necks, surrounded by a white fringe Like collar. Within the receptacles are a leries of cylindrical tubes, or asei, which (inlose tin sporidia, eight of which are contained in each tube, and each one is colourl< - and oval, without any division (7x8 /(). Winn tie is Leaves fall to the ground the sporidia soon arrive at maturity, and an d ■, d to fulfil their duty in the perpetuation of the spi oil . There is an earlier and imperfect stage [Leptothyriwn Coryli), in FUNGOID PESTS OF CULTIVATED PLANTS. 141 which the sporules are free in the receptacles (18 x 2 /.i), but the precise nature of their relationship is not distinctly known. Sacc. Syll. i. 1590 ; Cooke Hdbk. No. 2736 ; Tubeuf, Dis. 224. The above is not common enough or harmful enough to cause the least anxiety. Root Fungi. It has been known for the past fifty years — and Berkeley was con- tinually reverting to it, and asserting it, in the pages of the Gardeners' Chronicle — that the white fleecy mycelium often seen about the roots of orchard trees was injurious to them ; that it originated from dead stumps and buried wood, and attacked the roots of living trees when it was no Fig. 19. — Tree-root Rot (Armillaria mellea). longer a saprophyte, but became a parasite and crept up between the cortex and the wood, and ultimately killed the tree. This is now more generally acknowledged to be true, whatever the ultimate development of the mycelium might be, possibly some Agaric, and that dead wood and dead roots left in the soil when young trees are planted will sooner or later prove the source of great injury and destruction. It has been left to more recent- times to demonstrate that mycelium which originally, and in ordinary cases, was only a saprophyte could under favourable con- ditions become a dangerous parasite. Under such circumstances it will be seen that trees should never be planted in soil which contains the remains of dead stumps or dead roots, and whenever growing trees are discovered with this mycelium at the roots they should be removed and the soil sterilised before it is planted 142 FUNGOID PESTS OF CULTIVATED PLANTS. again. Diseased roots, if not too far infected, should be cleaned and pruned before replanting, and well washed with some fungicide, when, in some cases, they may possibly recover ; otherwise they should be burnt forthwith. Jonrn. B.II.S. xxix. 1904, p. xliv. Orchard Agarics. Armillaria mellea (Vahl). This very common Agaric grows in large clusters at the base of stumps and old trees, and often in orchards where the mycelium extends to and becomes parasitic on growing trees, causing great mischief. The fungus grows in dense clusters with a pale honey-coloured pileus or cap, two to three inches across and a paler stem four to six inches long, with a distinct collar or ring surrounding the stem above the middle and a profusion of white spores, which fall and settle on surrounding objects as a dense white powder. (Fig. 19.) The black strands of mycelium, thick as fine twine, and known as " rhizomorphs," are well known, and generally belong to this Agaric. Sacc. Syll. vi. 289; Mass. PL Dis. p. 202, fig. 47; Cooke Hdbk. No. 36, fig. 36 ; Cooke Illus. pi. 32. Pholiota squarrosa (Mull.). Dense tufts of this Agaric may often be seen at the base of trunks in orchards, and is capable of doing great injury by the mycelium becoming parasitic. The Agaric is similar in size and form to the above Armillaria, but both cap and stem are yellowish brown, densely clad with projecting brown scales, and the spores, and consequently the gills, are brown. The smell is stron Sacc. Syll. vi. 3093 ; Mass. PL Dis. p. 208 ; Cooke Hdbk. No. 297 ; Cooke Illus. pi. 367 ; Sow. Fung. t. 284. Tinder Polypore. Fomes fomentarius (Fries). It lb strongly contended by some writers that the woody Polypores which are common mostly on forest trees will attack fruit trees as wound parasites, and compass their destruction. One species is found onetimes on fruit trees, which become as hard as a wooden log. In hapi il omewhat resembles a horse's hoof, with a smooth upper surface of a dark brown colour attached firmly by the hack, so as to project like a bracket. The under surface is almost flat, or a little concave, pale, and punctured with minute pin-holes or pores close together all over tho surface. These pores contain the spores, which are snuff-coloured and profuse, o that fchej tall when mature on all surrounding objects like snuff. Thia [fi B wound parasite, the spores finding an entrance into its victim ire. through a wound, and afterwards developing on the surface. One oi these wound parasites is Femes fomentarius, which is common FUNGOID PESTS OF CULTIVATED PLANTS. 143 on Beech trunks and occasionally on fruit trees. All such fungi should be cut away and the wound dressed with gas tar. (Fig. 20.) V » < *-». '•« Fig. 20. — Fomks fomentabius. The woodcut is not by any means a good characteristic figure. Sacc. Syll. Hym. ii. 5409 ; Cooke Hclbk. No. 776 ; Joum. B.H.S. xxvi. (1902), p. 734, fig. 308 ; Mass. PL Dis. 185, 392. CURRANT-LEAF SPOT. Septorid JRibis (Desm.), PI. XII. fig. 31. This spot appears to be confined to the living leaves of the Black Currant, and is certainly common enough. The spots are small and irregular, brown then purplish, sprinkled with the minute dots of the innate conceptacles which are covered by the cuticle, which are exceed- ingly small, with a minute pore at the apex, through which the mature spores are ejected in a roseate tendril. The spores, or conidia, are very long and thread-like, curved, containing a row of guttules (50 /u long). In common with most kinds of leaf-spot, this affection is treated generally with great indifference, the general impression being that it only affects the leaf upon which it grows, and does not in any way influence the general health of the bushes. Known in France, Germany, and the United States. In New Zealand it is known as 'the Gooseberry rust. " After the crop is off Bordeaux mixture may be used, and should be again applied, full strength, before the buds break, early in the following season as a preventive. All leaves to be raked up and burned." Sacc. Syll iii. 2849 ; Cooke Hclbk. No. 1338 ; Grevillca, xiv. 76 v Joum. B.H.S. xxv. (1900), p. 143, fig. 144 FUNGOID PESTS OF CULTIVATED PLANTS. Currant Bleached Spot. Pkyllosticta ribicola (Fr.). The spots are sometimes found on the leaves of the Ked Currant, and are rather large and hleached, with a number of minute black conceptacles scattered over the surface like pin-points. The conidia are simple and small, oblong and colourless (15-17 fi long). Sacc. Syll. iii. 82. GOOSEBERRY-LEAF Sl'OT. Phyllosticta Grossularice (Sacc). The spots on the leaves of the Gooseberry are similar to those on the leaves of the Currant, but smaller, and with a circumscribing brown line. They differ also in the smaller sporidia, which are not more than one third the length of the foregoing (5-6 x3 /<). This species is known in most parts of Europe and also in North America, but is treated as though it were regarded as practically harm- less. Sacc. Syll. iii. 83. Another Gooseberry leaf-spot (Ascochyta Grossularice) is known in Europe with apparently two-celled conidia. Currant Anthracnose. wium Bibis (Lib.), PL XII. fig. 32. Although this species of leaf-spot is tolerated without complaints, it is sufficiently common, but not so injurious as most species of Anthracnose. I- generally affects the leaves of the Red or White Currant, on which it produces circular spots, sometimes confluent, and wholly brownish in colour. The pustules appeal on the upper surface of the spots, concealed In math tin' cuticle, beinj somewhat flattened and of a darker reddish - brown externally, but whitish within, and without any true conceptacle. The mass of spores is whitish, and is ejected when mature through a central opening in the cuticle. The conidia, or sporules, are oblong and curved (10x5 /•). In wel weather they may be seen oozing out in a tendril through the aperture in the cuticle. It is had policy to treat any of the species of Anthracnose with con- tempt. Seeing that they may give trouble at any time should a favourable ■ m occur: and it has ]>ro\ed to be very far from harmless in the United States, where the remedy recommended is spraying with one of the copper solutions. Sacc. SyU. iii. B694 ; Ma . PI. Die. 28G ; Cooke Hdbk. No. 1235. Qlasosporium curvatum, known in Holland on Black Currant leaves, has la i oidia (11-20x5-7 n). FUNGOID PESTS OF CULTIVATED PLANTS. 145 Gooseberry Cluster-cups. JEcidium Grossularice (Gmel.), PL XII. fig. 33. These cluster-cups seem to be rather erratic in their appearance, as in some years they can scarcely be found at all. They occur principally on the living leaves or the green fruit. Jl£.e spots on the leaves are yellow on one side and reddish on the othe"r, with a yellow border. The cups are clustered in the centre of the spots, and are rather long, with the usual white fringed margin. The a>cidiospores are bright orange, produced in chains, but freely separating into somewhat globose spores, with a finely spinulose surface (10-20 /* diam.). This is one of those fortunate species whose fate is not linked with any Uredo or Puccinia. Up to now no enthusiast has imagined for it a graminivorous bride, and for the present it has to run its course in single blessedness. The species is known in France, Belgium, Germany, Lapland,. Denmark, Switzerland, Asiatic Siberia, and North America. Quite recently it has been decided by authority that the proper Uredo and Puccinia are to be found on the leaves of species of Carex. Sacc. Syll. vii. 2787; Cooke M. F. 192; Gard. Citron. July 1881,. figs. 15-19 ; Mass. PL Dis. 95 ; Cooke Hdbk. No. 1620 ; Plow. Brit. Ured. 263 ; Gard. Chron. May 13, 1905, p. 304, fig. 126. Gooseberry Mildew. Microsphcera Grossularice (Lev.), PL XII. fig. 34. A little of the Gooseberry mildew appears every year, but it does not always proceed beyond the mealy or conidial stage. The living leaves become whitened and chalky, as in the allied species, from the interwoven mycelium, which spreads over the surface of the leaves. Its occurrence has been most observed in very dry seasons and on both sides of tbe leaves. The first stage is an Oidium, with its chain of conidia. The receptacles are always few and scattered, being small and globose as usual, and attached to the mycelium by a small bundle of fibres from the base. The circle of appendages which surround the conceptacle consists of from ten to fifteen colourless radiating slender arms, which are forked near the tips, each branch being again forked, and the extremities of all the branchlets split into two teeth, which are pointed, and not thickened as in some other species. The contents of the mature conceptacles are from four to eight ovate sacs, or asci, each of which encloses four or five hyaline sporidia, so that each conceptacle may contain from sixteen to forty spores. The mycelium of these mildews does not in the first instance establish itself within the substance of the leaves, and never enters to any appre- ciable extent. Hence it is an epiphyte, and has only to be destroyed to restore the vigour of the affected plants. It is in this class of diseases that the application of sulphur is likely to prove most beneficial. Sacc. Syll. i. 40 ; Cooke M. F. 240 ; Cooke Hdbk. No. 1922 ; Mass. PI. Dis. 95, fig. 15 ; Joum. R.II.S. xxv. (1900), p. 145. L 146 FUNGOID PESTS OF CULTIVATED PLANTS. American Gooseberry Mildew. Spharotheca Mors-ucce (Schw.). This disease has been widely and well known in the United States for scores of years, but only recently has visited Ireland, which entitles it to notice here. As a proof of its virulence, one American writer states : " The mildew of the Gooseberry is the most serious obstacle to the successful culture of the foreign Gooseberry in the United States." It first makes its appearance on the young half -grown leaves and the unfolding bud of the shoot. Then it has a cobwebby appearance, which soon becomes white and powdery. Soon after this patches may be found on the berries, usually on one side more than on the other. Later on the leaves, petioles, and young stems turn a rusty-brown colour, and become thickly coated with the fungus. The berries at the same time are covered with brown patches of mycelium, which may be readily peeled off. The conceptacles are developed upon the mycelium in this species, as well as on the Hop mildew, and the sporidia (15 /< long) are in like manner developed within the asci. Experiments made have shown that as a fungicide in this instance potassium sulphide was far more effective than Bordeaux mixture, lysol, or formalin, using one ounce of potassium sulphide to two gallons of water. Repeat the application every ten days till the fruit is nearly mature. r. Syll. i. No. 12; Grevillea, iv. p. 158; Journ. B.H.S. xxv. 1 890), p. 140, fig. 37 ; xxvii. (1902), p. 596, fig. 166 ; xxix. 1904, p. 102 ; 8. PI. Dis. 97. 362 ; Garcl. Chron. Oct. 2K, 1905, p. 305. Gooseberry Polvi'oke. Fomes Ribis (Fries). This hard woody Polyporus may often be found growing at the base of the .siems of old Gooseberry and Currant bushes, and has now the credit of being a true parasite. It consists of ;i hard woody pileus, almost hoof-shaped and often ether, one placed above the other, and from two to four inches aero 'Flu' upper surface convex, yellowish-brown, and when young minutely velvety, bul becoming bald and smooth when old, with con- <•• atric zoi The under Burface nearly plane, and pierced with innumerable minute puns of a brownish-grey colour. When cut in :io]i the fibrous flesh is of a rusty-brown colour. This fungus is perennial, and lasts from year to year, but is only found "D quite old hushes, which may easily he replaced l>\ more youth- ful .' . . Sacc. Syll. Hum. ii. No. 5427; Mass. PI. Dis. 186; Cooke Hdbk. No. 780. Raspberbi Cane Spot. Phylhstkta pallor (Berk.), PL XII. fig. 35. This -p >t Mo ii,. living Raspberry cane- was fir I observed by Berkeley many years ago, and was called Ascochyta pallor, albeit the conidia were not two-celled. FUNGOID PESTS OF CULTIVATED PLANTS. 147 Roundish or elliptical paler spots are formed on the canes, over which the dot-like receptacles are scattered immersed in the substance of the spot, which is pierced by the dot-like orifice. Around this opening the substance is a little raised and blackened, so as to form a kind of ring. The conidia are sausage-shaped, narrow and slightly curved, obtuse at the ends (14-18 x 4-5 /*). Has been very little observed, although apparently a true parasite. Hence it is not likely to give trouble, or it would scarcely have rested so long. Apparently only known in Britain and Holland. Sacc Syll. iii. 2206 and 4912 ; Berk. Ann. X. H. No. 193, fig. ; Cooke Hdbk. No. 1356. Raspberry cane blight, attributed to Coniothyrium Fuckelii, is more or less common in the Raspberry plantations of New York State, causing the plants to die about the time that the fruit is ripening. The fungus is known in Europe. Raspberry Anthracnose. Glmosporium venetum (Speg.), PI. XII. fig. 36. "We are not thoroughly convinced that this Anthracnose has occurred in Britain, although it is well known in Continental Europe, in the United States, and in Australia. On the leaves it produces large marginal spots of a honey colour, margined by a distinct purplish line ; towards the centre of the leaf the spots are smaller and rounded. On the petioles and young twigs the spots are more definitely elliptical and pallid, and on the young canes. The pustules are without any true receptacle, sunk in the substance of the leaf or stem, and the conidia are produced within these cells, elliptical and colourless (7-8 x 2-2 \ //.), often with two small nuclei, and ejected when mature through a fissure in the cuticle as a gelatinous boss or tendril. The conidia germinate readily and spread the disease. Young canes are not killed the first season, but succumb on the second, the fruit remaining small and shrivelled. Spraying with sulphate of iron solution and diluted Bordeaux mixture has been recommended. Nothing will save the canes when thoroughly attacked, and the only alternative is to burn and prevent the spread of disease. Sacc. Syll. iii. 3962 ; Mass. PI, Dis. 286 ; Tubeuf, Dis. 483. Raspberry canes are reported in Australia as suffering from attack at the roots of the mycelium of the very common clustered Agaric (Ilijpho- loma fascicular e), so plentiful about old stamps in this country. "Raspberry Cane Blight," see Joimi. R.H.S. xxviii. p. 288. Raspberry Brand. Phragmidium Bubi-Idcei. This very interesting brand, or rust, of the Raspberry, more often makes its appearance on the wild than upon the cultivated plants. In fact, it never has been an orchard pest, and yet it has been long enough known to have been called by at least thirteen names. l2 148 FUNGOID PESTS OF CULTIVATED PLANTS. It is supposed to have a species of Cluster-cups, just to save the con- sciences of the uredinists, although nothing like a Cluster-cup. This is the old Uredo gyrosa, with the pustule forming a little kind of ring which is indented in the centre. /Ecidiospores (?) globose, rough, yellow, (20-28 p. diam.). The uredospores form little pustules, scattered, or sometimes gathered in circles, the spores being spherical or ovoid, rough, and orange-yellow (16 22 n diam. i. The teleutospores are the most imposing, being produced in tufts or clusters, the upper portion, or the proper teleutospore, being elongated, cylindrical, rounded at each end, or with a hyaline wart like apiculus at the apex, divided transversely into from six to ten cells (90-140 x 20-35 /.i), externally warted, and of a dark brown colour, with a long colourless stem (110-160 x 17-20 /i), a little thickened below, straight or curved, and a little flattened laterally. Each cell is capable of separate germination, as if it were an individual spore. Known in Frauce, Belgium, Ardennes, Switzerland, Germany, Finland, Austria, Lapland, Italy, and North America. Sacc. Syll. \ii. 2626 ; Mass. PI. Dis. 258 ; Cooke M. F. 201, f. 43 ; Cooke Hdbk. No. 1459 ; Grecillea, iii. t. 45, fig. 9 ; Ploicr. Br. Ured. 226. Little Strawberry Spot. Phyllosticta fragaricola (Desm.), PL XII. fig. 38. This is one of the ordinary forms of spot on Strawberry leaves in which the spots are small, rounded, and whitened in the centre, with a blood-red margin. The conceptacles are few upon the spots, and dot-like. The conidia, or sporules, are oblong and minute (5x2 /x). It is noteworthy that in so many of the species of Phyllosticta, or spot with minute spores, we should have similar and corresponding spots of the Septoria type with long thread-like spores, that is to say, there may be on the same kind of leaves spots precisely similar, which in one case produce minute spores and in another long and thread-like spores, the difference being entirely that of the fructification. It has been suggested that the perithecia which at an early period produce minute sporules in;iy at a later period produce thread-like sporules ; but this is only con- jecture without e\idence. And yet future knowledge of the life history of these parasites may make it all plain. Sacc. Syll. iii. 219 ; QreviUea, xiv. 73. A leaf-spot precisely similar is known in Portugal and Italy (Asco- chylit Fragaria) in which the sporules are ellipticali (12-16 X 8-4 n) and two-celled. Has appeared also in the United States, and threatens mis- chief. S'l i;\\\ BERRY-LEAF Sl'OT. Septoria Fragaria (Desm.), PI. XII. fig. 39. This spot is familiar upon all Strawberry plants, hut commonly in a sterile condition. It occurs upon the upper surface of Strawberry leaves FUNGOID PESTS OF CULTIVATED PLANTS. 149 as circular brown spots with a reddish-brown margin. The conceptacles are very minute, sprinkled over the spots as little black dots with a rather broad pore at the apex through which the mature conidia are expelled in a whitish tendril. The conidia, or spores, are long and cylindrical or thread-like, with three transverse divisions and colourless (about 50 n long). It is unknown if any and what relations subsist between the several species of fungi which thrive with us upon Strawberry leaves. It has only been supposed that there is some connection, but it has not been demonstrated. Sacc. Syll. iii. 2767. Strawberry Anthracnose. Glceosporium Fragarice (Lib.), PI. XII. fig. 40. This disease is not at all uncommon on Strawberry leaves, but has never caused anxiety, since it was not credited with the power of inflicting serious injury. The spots are reddish on the upper surface, without any determinate outline. Upon these spots appear flattened blackish pustules, which nestle beneath the cuticle. The mass of conidia form a greyish nucleus within the cavity of the tissue. The conidia, or spores, are cylindrical, obtuse, and contain a row of four or five guttules (26-42 x 4 fi). There is no genuine conceptacle, but the surrounding cells are discoloured, and when mature the conidia ooze out at the apex of the pustules in globules or tendrils during moist weather and are washed over the foliage. All species of this genus are suspicious, and we doubt if this is really so innocent as has generally been supposed. It is known in France, Belgium, Germany, and the United States. .Sacc. Syll. iii. 3690. Stbawbebby Spot Mould. Ramularia Tulasnei (Sacc), PL XII. fig. 41. This fungus spots the leaves in a very similar manner to the ordinary leaf-spot. They are rather small orbicular white spots with a broad definite dark reddish margin, but without any dots. A white mould is seated upon the spots, which produces little bundles of colourless threads, and these develop at their tips cylindrical hyaline conidia which are straight, with one or two cross divisions (80-35 x3-4 /j). What appears to be the same fungus was known here for some years under the name of Cylindrosporium Grcvilleanum. The life history of this fungus has been investigated in North America, and hence we know more of it than of most leaf-spots, and that this fungus constitutes the conidia of another fungus, which appears later on and is known as Sphcerella Fraga/ria. For our purpose we may treat them as two separate diseases, with different manifestations and different treatment. The mould is known in Britain, France, Italy, Holland, and North America. 15(1 FUNGOID PESTS OF CULTIVATED PLANTS. In this stage it is more likely to submit to treatment by fungicides than in the more mature or resting condition. S . Syll. iv. 988 ; Sacc. F. Ital. t. 1006 ; Mass. PI Dis. 107. Ripening fruits are liable to attack from Oidium Balsami, already v/r, p. 84). Strawberry-leaf Blight. Spharella Fragaria (Sacc), PI. XII. fig. 42. When a spot first appears on a young leaf it is brownish or reddish, l hen becomes circular with a dead white centre (3-6 mm.) and broad purple border. Subsequently conidia are produced as already described (Bamularia Tulasnei), which for some time are produced in succession in mi the same threads. If these conidia fall on a fresh leaf surface they germinate in a few hours. In the latter part of the season the mycelium becomes compacted into sclerotia, which are capable of germinating and producing a crop of conidia in the spring. Perithecia are developed in late autumn, but are not matured until the spring, upon the white centre of old spots. Asci are produced within tin se perithecia, each containing eight oblong colourless two-celled sporidia (15 x8 4 /<). The fungus passes the winter under three forms : (1) as mycelium in the leaves, \'1\ as sclerotia developed from the mycelium, (3) as ascospores produced in the perithecia. The remedies suggested are a solution of sulphide of potassium one ouuce to eight gallons of water. Also the copper solutions. Burning of il spotted leaves which may carry the disease over to the spring. Known in Europe- — in France, Germany, and Italy — as well as in the United States. U.S.A. Exp. St, i. Cornell, xiv. Dec. 1889 ; Sacc. Syll. i. 1951 ; Mass. PI. Dis. 107, fig. is ; Tubeuf, Dis. 215, fig. S'ri;\\\ l;i;i;l;\ MlhDKW . Spharotheca Humuli (DC). A while mould on Strawberries was recognised by Berkeley in 1854, when be imagined il was the same species as bad been Known on Turnips. AJterwardf th< occurrence <>f the same mildew in America led to its further in tion, and it was discovered at Length to be none other than ;i form of the will -known mildew of the Hop. In this country only th< conidia! condition had been seen, which was a simple Oidium, some- what Like that of the Vine. <>n the other hand the perfect fruit was found in America, so thai between L892 and 1898 it became established that the fungus of the Strawberry mildew was thai known as Sphcsroth Humuli (or, as formerly termed, Sphorotheca CtUtCtgnei), the cause of the Hop mildew. (Pig. 21.) In the firsi stage il attacks the leaves, causing them to curl, so as to appear as if Buffering for lack of water. At this time the mycelium FUNGOID PESTS OF CULTIVATED PLANTS. 151 spreads over the under surface as a white felted mould, from which arise the short branches which bear the chains of conidia (30-35 x 20-24 /*). The mycelium sends suckers into the epidermal cells of the leaf whence to obtain nourishment. Subsequently to its appearance on the leaves the mildew spreads afterwards into contact with the fruit. Later in the season the second form of fruit is developed, after the manner of the Rose mildew, Pea mildew, and others of its kind. These are in the form of minute globose conceptacles, which become dotted over the mycelium, each containing a single ascus which encloses eight sporidia. These conceptacles are only sparingly produced, and those generally occur on the petioles of the leaves, and, like those of the vine mildew, Fig. 21. — Sph^rotheca Hdjiuli. a. Conidiophores. ( x 200.) b. Conidia. c. Conidia germinating. ( x 300.) d. Asci and spores. ( x 350.) perhaps in this country not at all. Doubtless the mildew is increasing with us, and complaints are being heard of it in Strawberry-growing localities. Some varieties stand the chances much better than others. Predisposing circumstances are affirmed to be sudden changes of temperature, especially a decrease during the night or a cool temperature followed by sunny weather. Experiments made by two fungicides seemed to afford satisfaction, viz. (1) one ounce of carbonate of copper and five ounces of carbonate of ammonia dissolved in a quart of hot water and then mixed with sixteen gallons of water when cold. (2) Dissolving a quarter of an ounce of sulphide of potassium in a gallon of water. Spraying wilh either of L52 FUNGOID PESTS OF CULTIVATED PLANTS. those mixtures is therefore recommended, especially the first ; but promp- titude must be used whilst the mildew is on the leaves, since it is useless when it has obtained a hold upon the fruit to attempt to save the crop. . Syll. i. 8; Cooke Hdbk. No. 1911 ; Berk, Gard. Chron. 1854, p. 286; Journ. B.H.S. xxv. (1900), p. 182, figs. 35, 36; Journ. Q.M.C. 1904, p. (30. PESTS OF THE VINERY AND STOVF The two sections of this communication treat of the fungoid diseases (1) of the Vine, and (2) of other plants cultivated in the hothouse. The pests which flourish at this high temperature seldom cause any trouble under other circumstances ; but the close, heated, and moist atmosphere of the stove is especially favourable to the development of fungus para- sites, and great care should be taken to recognise their earliest appear- ance, and hold them in check. Vine Leaf-spot. Septoria Badhcmi (Berk.), PI. XIII. fig. 2. This is not a common parasite, although we met with it several times about twenty years ago. It was first recognised in 1858, forming little brownish spots on the leaves, upon which were seated a few of the dot-like conceptacles, which occur in clusters on either side of the leaf. On one occasion we found the spots to be wholly marginal, becoming confluent around the greater portion of the leaf. The conidia, or sporules, are elongated or some- what club-shaped (35-50 /x long), with a few r minute granules, and they appear to be rarely, if ever, septate. Syll. iii. 2581 ; Cooke, Hdbk. No. 1309 ; Berk. & Br., Ann. N.IL. No. 748, t. 15, f. 9; Thiim. I'll:. Wein. p. 180. Small Vine Leaf-spot. Phyllosticta Badharm (Cooke), PI. XIII. fig. 1. Not fewer than fifteen other kinds of leaf-spots have been described as Occurring "li living vim-haves, in addition to nine species of anthracnose. This is a formidable List; but only one other has occurred in Britain, which answered in externa] appearance to the above description of Septoria Badhami, vrith the distinction that the conidia, or sporules, were minute (6 7x2//); and, as we issued specimens of it under that name, we have since called it Phyllosticta Badhami. (Journ. B.H.S. 1878, p. 98.) The other described ipecies of Vine leaf spot maybe briefly enume- rated hi i< . a "ii' or other of them may occur at any time. Italian Leaf-spot, Phoma Negriana (Thiim. ), on living vino-leaves in Italy, has sporules 5-7 X 8 '•>[, y. Mildew Leaf-spot, Phoma succedanea (Pass.), on vine-leaves in company with the mildew, has occurred in Italy with sporules 5 x2^/t. PL. XIII. PESTS— VINERY. FUNGOID PESTS OF CULTIVATED PLANTS. 153 American mildew leaf-spot, PJwma ampelogena (Sacc), has been found in the United States to follow the American mildew on vine-leaves. Sporules 4 x 3 /x. Vine leaf-spot, Phyllosticta Vitis (Sacc), found in Italy on living vine-leaves, with sporules 6 x 3 /x. Labrusca leaf-spot, Phyllosticta Labruscce (Thiim.), is an American species, which attacks the leaves of the Labrusca grape. The sporules are large, 9-11 x 6-7 /x, on small brown spots. Italian Vine leaf-spot, Phyllosticta viticola (Sacc), appears to be confined to living vine-leaves in Italy. The sporules are 5 x 2^ ju. Leveille's leaf-spot, Phyllosticta Leveillei (Cooke in Journ. B.H.S. 1878, p. 92), was described by Leveille (in Ann. Sci. Nat. Bot. 1846, v. p. 279) and specimen preserved in Berkeley Herbarium, with sporules about 10 /.i long. Known hitherto only in France. Carolina vine-spot, Phyllosticta viticola (B. & C), forms large spots on the leaves of Vitis vulpina in Carolina. Sporules 8-9 x 4 p. Ellis's Labrusca leaf-spot, Ascochyta Ellisii (Thiim.), on leaves of Vitis Labrusca, has bicellular sporules 6-8x5-6 /t/. Saccardo's leaf-spot, Ascochyta ampelina (Sacc), on vine-leaves in Italy. Sporules iwo-celled, 10 x 3 ^. Curtis's Vino leaf-spot, Sacidium viticola (Cooke, Journ. B.H.S. 1878, p. 92). Specimens from North America were distributed under the name of Septoria viticola. Sporules globose, 10 /j. Texas melanose, Septoria ampelina (B. & C), on leaves of Vitis vulpina, known in Texas and S. Carolina, with sporules 30-50 /n long. Small vine leaf-spot, Septoria vinea (Pass.), has occurred in Italy, with sporules 12-18 xH/u. Sorokin's vine-spot, Sphac'eloma ampelinum (Sorok.), is a Russian species but little known. Grape Red Spot. Glceosporium rufomaculans (Berk.), PI. XIII. fig. 3. This spot was first recognised on Grapes in 1854, and. since that time it has fortunately occurred but rarely, especially as it is one of the kind known as anthracnose, and they are virulent diseases to deal with. It forms a rounded spot of a sienna-brown colour on the fruit, preserving constantly a definite outline. This spot separates readily from the subjacent pulp, in consequence cf a copious crop of mycelium, the threads of which form the radii of a circle. The surface is rough with little raised orbicular reddish perithecia, or conceptacles, for there are no true perithecia, which are arranged in circles. The conidia are pro- duced within the- conceptacles or cells, and are oblong, without any division as yet observed, but constricted in the middle, and colourless (15-20 p long). In age the false perithecia fall away, leaving a little aperture, the border of which is often stained black. We have assumed this to be a Glceosporium, most certainly not Ascochyta, as first described, but we have not been fortunate enough to meet with it. It seems to be distinct from Glceosporium uvicolum on 154 FUNGOID PESTS OF CULTIVATED PLANTS. < rrapes, but appears to be a form of Glceosporium fruGtigenum, which is said to occur on Grapes as well as on Apples. rd. Chron. 1854, p. G76 ; Cooke, Hdbk. No. 1358. Australian anthracnose, Glceosporium bicolor (McAlp.), is the Apple- rot of Australia. Grape Rot. eosporium uvicolum (Berk.), H. XIII. fig. 4. There is some confusion in the records of this species, which has also been called Glceosporium laticolor, but the proper best of that species is the Peach and Nectarine. (S\ X 800' b c \a> Fio. 22. Amu; o] mi Vine, {Gardeners' Chronicle.) The spots are always of a pale orange, with an almost white spot in the middle. The tendrils of spores, or conidia, are similar in colour, and the conidia arc Larg< c than in the species upon Peaches (26 /* Long). Fortunately .i nn rare specit 3, and is not likely to cause much annoyance. /;,/-/.-., Gard. Chron. 1864, p. 676; Sept. 9, 1871, p. 1162. ( .i; \ri: A', i in; LCNOBB. Glceosporium ampelophagum (Pass.), PI. XIII. fig. 5. This attacks Grapevines in Italy and the I'nited States, but until •ntly there has been im record of it in Britain. It attacks all the FUNGOID PESTS OF CULTIVATED FLANTS. 155 green parts, and internally exhibits very little mycelium ; the pustules are without definite receptacles, and the conidia are produced on short stalks within definite cells ; when mature they escape by rupture of the cuticle, and lie like a crust on the surface until dissolved by moisture (5-6 x 2^ p), when they float away to infect other parts. (Fig. 22.) Gard. Ckron. July 8, 1893, fig. 10 ; Mass. PL Dis. p. 279 ; Sacc. Syll. iii. 3755; Thiim. Pilz. Wcin. p. 9 t. 3, f. 24; Thiim. Pock. d. Wein. (1880) ; Tubeuf, Dis. p. 484. Fresh compost at the roots recommended, Gard. Citron. Aug. 27, 1904, p. 153. White rot of Grapes, Coniothyrium diplodiella (Speg.), occurs on the fruit, leaves, and rarely on twigs. It is uncertain whether it is truly a parasite. The coloured sporules are 7-11 x5^ p. This pest has recently been investigated in Hungary by Istvanfn, and the results published in " Annales de l'Tnstit. Ampelologique Koy. Hongrois," ii. 1902, with 24 coloured plates, in which it is claimed to be a destructive parasite. Squirt Berry, Phovia tuberculata (McAlp.), is an Australian species. Grape Hendersonia, Hendersons tenuipe? (McAlp.), occurs on ripe Grapes in Australia, but we doubt its parasitism, and also whether it may not rather be a Pestalozzia, with delicate cilia not observed. It need cause no alarm in Europe. Vine Leaf-spot Mould. Cercospora viticola (Sacc), PI. XIII. fig. 6. Massee says simply that it forms " brown spots on vine-leaves, and is most abundant during a damp season. Most abundant on the lower shaded leaves." Still we are in doubt whether he records it as British, and although we have seen foreign specimens, we have had none reputed to be indigenous. The spots occur on both sides of the leaves, and are somewhat circular or irregular (2-10 mm.), becoming ochraceous, not distinctly marginate ; threads on the under surface in tufts (50-200 x 4-5 /j), septate, ochre. Conidia elongated, attenuated upwards, three- to four- septate (50-70 x7-8 /u), with a tinge of olive. This is recorded for France, Germany, Portugal, Austria, and Italy, but must be quite distinct from Isariopsis clavispora, with which it has been confounded. Sacc. Syll iv. 2200 ; Mass. PI. Dis. pp. 319, 439. Another species {Ccrcospora RiJsslcri), with shorter, obtuser, and more cylindrical conidia, is recorded on living vine-leaves for France, Portugal, Austria, and Italy (50-60 x7/<). A species called Ccrcospora sessilis (Sorok.) is recorded from Russia. 156 FUNGOID PESTS OF CULTIVATED PLANTS. Vine Leaf-tuft Mould. Isariopsis clavispora (B, & C), PI. XIII. fig. 7. This appears to be entirely an American species, but authors have confounded it with Cercospora viticola, and may do so again. We are not aware that it has been found on any other living leaves than those of Vitis Labrusca, and was first described by Berkeley. The spots are brown, and mostly irregular. The compacted hypha are closely united in the lower portion, but become loosened and flexuous near the apex. The conidia are narrowly clavate, round at the apex, and multiseptate (as many as 7-9), hyaline and attenuated downwards, but brownish above (100 x 5-6 /a), each cell sometimes including a small guttule. Careful examination will convince anyone that the conidia are attached by the thin extremity, and that they can hardly be regarded as a topsy turvy condition of Cercospora viticola. Sacc. Syll. iv. 2998 ; Berk. & Curt., Grcvillea, iii. p. 100, No. 619 ; Thiim. Pilz. Weill. 177, t. 5, f. 7 (bad). Other black moulds, of which many have been named in connection with the Vine, appear to be saprophytes, with the exception, perhaps, of Fumago vagans, which has a wide range of hosts, and may soon be dis- posed of, if it ventures to appear in a well-ordered vinery. English Vine Disease. Oidium Tuckeri (Berk.), PI. XIII. fig. 8. The ordinary English Vine disease was first observed in 1845 at Margate by a gardener, Edward Tucker, and it is known to this day as Oidium Tuckeri. In 1853 it appeared in Spain, and a year later in Portugal. It was first observed in Madeira in 1851, and was not long in spreading through the continent of Europe. The disease is too well known to need description. When the shoots are struck they become spotted with dark grey or rust colour ; the leaves also become spotted, and covered with a cottony substance of fine fila- ments, as seen under the microscope. The Grapes are covered with what yppears to be a white powder, like lime, a little darkened with brown. The mould, like other species of Oidium, has a creeping mycelium, which supports erect fertile tbu-eads, and these latter become differentiated into chains of colourless spores or conidia. Some writers are of opinion that this disease is the same as the " powdery mildew " of the United States the full development of which is known under the name of Uncinula spiralis ; but as the receptacles, or the Erysiphe condition, have never been found in Europe, it is still a doubtful point. It is more than probable that the Oidium Tuckeri, as known to us, is an imperfect fungus of which the full development would naturally be a very close associate of Uncinula spiralis, if not really the same species. PESTS-VINERY, &C. FUNGOID PESTS OF CULTIVATED PLANTS. 157 As an epiphyte, the application of sulphur has been the only success- ful remedy, or sulphur in combination with lime. Garcl. Chron, May 15, 188G ; 1847, p. 779 ; 1878, p. 74. Journ. B.H.S. 1878, p. 68. Thiim. Pilz. Wein. p. 1, t. 3, f. 1. Powdery Mildew of Vine. Uncinula spiralis (B. & C), PI. XIV. fig. 13. American botanists are generally satisfied that this vine disease of theirs is a fruitful development of the English vine disease, which we only know, in the conidial form, as Oidium Tuckeri, for which reason, therefore, it is entitled to some notice here. It forms white or greyish patches on the surface of the leaves, young shoots, and fruit. This is composed of the interwoven threads of the mycelium, from which afterwards arise short erect branches, the upper portion of which becomes converted into a chain of conidia, the final one, which is the oldest, falling away when mature, giving to the white patches a still more powdery appearance. Towards the end of the summer the globose conceptacles make their appearance amongst the mycelium, at first yellow, afterwards dark brown, attached at the base by delicate threads. Encircling the base, a series of spreading, straight, simple appendages radiate around the conceptacles, in number from ten to twenty, the tips of which are hooked or spirally twisted, and the lower part, next the conceptacles, coloured. The asci, or sacs, within the conceptacles, enclose from four to six elliptical sporidia (20 x 8-10 H ). Journ. B.H.S. 1878, p. 68 ; Thiim. Pilz. Wein. p. 183 ; Grevillea, iv. 159 ; Gard. Chron. 1878, p. 74 ; Mass. PI Dis. pp. 93, 360, fig. 14 ; Tubcuf, Dis. p. 176. In the United States another species of the same genus {Uncinula subfusca) attacks the living leaves of Vitis Labrusca. Australian Vine Mildew. Erysiphe vitigera (C. & M.). This is the vine mildew which in Australia corresponds to the powdery mildew of the United States, and to our own Oidium Tuckeri. In its early manifestations, and the conidial stage, it might be taken for Oidium Tuckeri, and probably was so accepted before the discovery of the perfect fruit. The first stage is the creeping mycelium and white mould, which covers the leaves, wholly or in patches, and this is followed by the presence, amongst the mycelium, of the little globose conceptacles, attached at the base, and furnished with a circle of appendages or flexuous threads, as in other species of Erysiplie, such as the one upon the Garden Pea, but less distinct and more interwoven with the mycelium. The receptacles contain four pear-shaped sacs or asci, each of which contains two sporidia (18 x 9 /j), which are elliptical and colourless. It was first made known and described in 1887. 158 FUNGOID PESTS OF CULTIVATED PLANTS. The same remedies are recommended as have been applied in the case of tin- English vine mildew, and doubtless the persistent application of sulphur will bring its reward. , xv. 98; S ■ Syll. x. 1571. I'.i.u k Rot of Grapes. GtUgnardia Bidwellii (Viala), PL XIII. fig. 9. Doubtless one of the most destructive of our American vine pests, which manifests itself in variable forms, found its way into Europe in 1886 with imported vines. Xoung shoots and leaves are first attacked, under the form of small brownish blotches. A fortnight later the fruit shows symptoms of disease by the appearance of small blackish spots; afterwards the fruit turns black, shrivels, and becomes hard. At this stage the surface of the ] latches is seen to be studded with little black points, indicating what are termed the pycnidia form of the disease, or the summer fruits. These receptacles contain innumerable minute bodies, or stylospores, which are produced in the interior, and when mature ooze out through a pore at the \ (7 8/i long). This is the condition which was first known, and was then called Phoma uvicola. The stylospores, after their escape, are carried about by moisture over the surface of healthy Grapes, where they ;it once, enter the tissues, form a diseased spot, and thus dis- tribute the disease. Later on other tonus of summer fruit supervene, until the final or highest form of fruit appears on the diseased Grapes lying on the ground during the winter. In this stage the Bp iridia are produced in cylindrical cells, or asci, and come to maturity in the spring. They arc almost elliptical, without division, and colourless (12 17 x •!.', .">/<). In the United States spraying with Bordeaux mixture is much relied upon. Oard. Chron. January 26, 1895, p. 101, fig. 18 ; Mass. PL Dis. p. 105 ; mi. /'//:. Wein. p. L56, I 11 ; Tube <. Dis. p. 216. Vine Sclerotini \. Sclerotinia Fuckeliana (De Bary), PL X.IV. fig. 11. This \ine pest appears also under two or three forms, the earliest being that of a mould, representing the conidia, and not uncommon on • -ther plan! rail as the vine. In days when it wi regarded as a plett or perfect fungus, it was called Botrytis cinerea, and thai name ind to be ometi • mvenienl now [pp. 71, 72). Thi conidia form appears in tufts of a greyish colour, sometimes in Th< Ot threads are Stout, erect. dingv olive, some- what branched in the upper portion, the tip of each branch bearing a tewhal tuft or cluster of broadly elliptical conidia (8 l) x (i /i). The mycelium of the mould traversing the tissues of the host beoomes into Dumerous small black olerotia, which pass a period of ■ and afterwards prod q the conidial fruit, or the cup-like form. The little fleshy cups, or Sclerotinia, resemble a very miniature wine- FUNGOID PESTS OF CULTIVATED PLANTS. 159 glass, with a long slender stem, the cups not more than one tenth of an inch across, but the stem possibly more than half an inch long. The inner membrane of the cup consists of cylindrical asci, or cells, packed closely side by side, each containing right sporidia, which are the perfect fruit. The sporidia are elliptical, colourless (10-11 x 6-7 fi). Spraying with dilute Bordeaux mixture destroys the conidia. Leaves and other debris likely to contain the sclerotia should be collected and burnt. Sacc. Syll. viii. 799 ; Mass. PI. Dis. p. 148, fig. 31 ; Thiim. Pilz. Weiii. pp. 195, 197; McAlpine, Dep. Agri. Vict. p. 29; Garcl. Chron. Jan. 20, 1906, p. 42. American Downy Mildew. Plasmopara viticola (B. & C), PI. XIII. fig. 10. The American mildew is not of the same character as the English vine mildew, inasmuch as whilst the latter is a surface mould in the first instance, the former is an innate rot-mould, like the Potato and Onion diseases. Not only is it North American in its origin, but it has already found its way over to Europe and into the British Isles. This mould attacks all the green parts of the vine. The mycelium traverses the tissue of the leaves before there is any external manifesta- tion. In time erect threads arise from this mycelium and find their way in tufts through the stomata into the external air, and produce conidia. From five to eight of these fertile threads will issue through a breath- ing pore, and form a tuft of white mould. Hence the under surface of the leaves soon exhibits downy patches of the mould, and it came to be called " downy mildew." The upper portion of the threads is branched in a peculiar manner, and the conidia are borne on little points at the tips of the branches. The primary branches alternate ; the secondary branches three- to four-furcate, the ultimate branchlets pointed, straight, short, usually four, bearing the ovoid conidia (from 8 x 12 n to 7 x 30 fi). In time the conidia evolve from their contents five or six active zoospores, armed with two cilia, by means of which they move about. The other mode of reproduction is by resting-spores, which are sub- globose (30-35 fi diam.), with a brownish smooth or slightly wrinkled coat. The most effectual remedy yet devised is spraying the vines with a solution of sulphate of copper and lime. Tabcuf, Dis. p. 128 ; Sacc. Syll. vii. 806 ; Mass. PI. Dis. 69, fig. 9, p. 354; Gard. Chron. January 2, 1894, July 21, 1891; Farlow, Hull. Buss. Inst. 1876, p. 415 ; Journ. li.lLS. 1S78, p. 73 ; Thiim. Pilz. Wein. p. 166 t. 1, f. 5. Vine Root Clubbing. Plasmodiophora Vitis, PI. XIV. fig. 12. One of the latest importations of vine diseases is that known as " vine clubbing," which does not differ greatly from the clubbing in 1G0 FUNGOID PESTS OF CTLTIVATED PLANTS. Turnips. Probably it is quite true that some of our vine-growers hav< known ii for years, but did not regard it in any serious light. The vine roots in question are swollen into large somewhat glohose nodules, as large as the fist, the surface heing rough or warted, with obtuse projections, and when cut the cellular interior is found to contain a mucilaginous substance, not unlike the plasmodium of some species of M\ xomya I In all essentials the new parasite conforms to the Turnip club-root, or '• fingers and toe-." In its earlier stages a section of the distorted root will exhibit the ordinary cells enlarged to very many times their original dimensions, and filled with a slimy mucilaginous fluid, of a yellowish colour, capable of being drawn out into slimy strings, but with no trace of the ordinary fungus threads, or mycelium, which usually accompanies fungoid parasites. Later on, towards autumn and winter, the cells present a somewhat different appearance, being no longer filled with the structure- less mucilage, but differentiated into a host of nearly spherical bodies with a distinct cell-wall, and possessing all the characteristics of conidia, or fungus spores. These bodies are produced in enormous quantities, and of an extremely minute size, but without colour. By patient research and continued investigation, it may be possible to trace the germination and development of these conidia, which, it may be presumed, do not differ materially from those of the Turnip club-root. In the slime fungi (Myxomycetes) the spores or conidia on germination give origin to one, two, or more naked cells which possess the power of movement, due to the protrusion of pseudopodia, or the presence of a (ilium : these are known as swarm-cells. They possess a nucleus, multiply by bipartition, and eventually coalesce to form a plasmodium in this manner. After the production of numerous swarm spores by repeated bipartition. little groups are formed, by the close approach of two or more of these bodies: these groups often disperse again, but eventually the components of a group coalesce, and lose their individuality. This coali -cence results in the formation of a small plasmodium which possesses the power of attracting surrounding free swarm-cells, which at once Coalesce and augment the bulk of the plasmodium. This power of ation and formation of a plasmodium originated the name of Plasmodiophora, <>v M pla modium-bearer," for the present genus, the -limy mucilaginou i I" Ing the plasmodium condition of the parasite. I'.\ i eri( oi gradations it ha- been demonstrated that each atom of protoplasm cret p& out of its envelope and becomes a zoospore, with a kind of hairlike tail. It may be conjectured how those creeping bodies, when released from an old clubbing, remain in the soil, progress to other and 'hbouring i" it . and thus continue to perpetuate and diffuse the Each cluh rout i- therefore a centre from which the disease may ■ a'j. h i ly probable that any of the numerous fungicides will be of any avail to dislodge the parasite when once it has obtained po • ion. The only feasible remedy is to extirpate by burning every atom of infected roots, and not to plant again on the same spot without wrholi of the soil, and replacing it by fresh and unpolluted th. This may seem to he a drnstic measure, hut with such a foe only measures which are thorough can be effective. FUNGOID PESTS OF CULTIVATED PLANTS. 161 Whether a Californian vine disease, which is attributed to Plasmodio- plwra californica, is the same as the present species, we are unable to determine. Gard. Chron. June 17, 1893 ; Mass. PL Dis. p. 338 ; Mass., Ann.Bot. ix. p. 421, pi. ; Tubcuf, Dis. p. 528. Another vine-root parasite was described some years ago under the name of Eosslcra liypogcea, which was found on vine roots after they were really dead, not only in Austria, but in this country. They were little rounded fungi, like the head and upper portion of a large pin, but unfortunately, when they were submitted to that eminent lichenologist, the late Rev. W. Leighton, he pronounced them to be a well-known lichen called Coniocybe pallida. Gard. Chron. Dec. 22, 1888, fig. 105 ; Thiim. Pilz. Wein. p. 210, t. 4, f. 9. White Root-kot. Dematophora necatrix (Hartig), PI. XIV. fig. 20. This root disease, which affects the vine as well as other plants, was originally known by the above name, representing the imperfect condition in which it is usually found. The mycelium spreads rapidly underground, and when it comes in contact with the rootlets of a plant it kills them, and gradually works its way upwards into the larger portions of the root. Sometimes, after travelling upwards, it bursts through the bark at the base of the trunk in a white woolly mass. During its progress minute sclerotia are formed, which originate dark- coloured, rigid, bristly conidiophores bearing numerous conidia at their tips. Another kind of fructification is sometimes found on decaying roots in the form of pycnidia, or conceptacles containing stylospores. The highest or ascigerous form of fructification is more rare, and consists of large black perithecia which include asci and sporidia, and are surrounded by the bristly conidiophores. In this condition it has been characterised under the name of Bosellinia necatrix (Prill. & Del.). Spraying is out of the question in such a case, and no cure can be hoped for when the mycelium is once established. If the disease appears, the affected plants should be isolated by trenching around them. Hartig & Somer. Dis. p. 82, with figs.; Viala, Mon. with 5 plates; Mass. PI. Dis. p. 118, fig. 21. Discolouked Vine Leaves. Discoloured Vine leaves are continually turning up without furnishing any clue to the cause. These are mostly discoloured in large bright blotches, which are sometimes yellow, as in some forms of the " Californian Vine disease ; "-or dark red, as in the " Sicilian Folletage ; " or red, brown, and yellow, as in the Italian " Mai Nero." They appear to give evidence of some form of organic disease, and yet to evade all microscopical scrutiny, and after many years to remain as great a mystery as ever and consequently without the suggestion of a remedy. U.S.A. Report Dev. Agri. 1892. ]62 FUNGOID PESTS OF CULTIVATED PLANTS. CONSERVATORY PARASITES. Separate from the fungi which affect garden plants there are a few that are troublesome in the stove and conservatory, and these could not be excluded from the present enumeration. In this connection the list might have been much extended, but the persons interested would be rilv limited, as compared with those who confine themselves to out- door culture. Sooty Mould of Orange. Fumago vagans (Pers.), PL XIV. fig. 21. This black mould is familiar enough, as it occurs on the foliage of numerous trees in this country, and especially such as are subject to honeydew. It forms black patches on the leaves, to such an extent as to form a crust ; but in this condition it is simply an imperfect fungus, and may develop into a species of Capnodium or MeUola, as the case may be. Tbe creeping mycelium is branching, and closely adnate to the matrix, sometimes confluent and forming cellular ganglia, or torulose, like a string of beads, -constituting an effused thinly membranaceous stratum, which is apt to flake off when dry, and resembling a coating of soot. Short fertile branches arise from this mycelium, which are more or less branched ; conidia at the tips of the branches, often forming short chains, sometimes one-celled, usually two-celled, and sometimes three-celled (5 l"»/( long), dark brown. It is found throughout Europe and North America, and in parts of A -it. but it is scarcely probable that we shall be troubled with the advanced stages in this country, whether Capnodium, MeUola, or any of their kindred. 8acc. Syll. iv. 2618 ; Journ. fi.II.s. iv. 251 ; U.S.A. Dep. Agri. Bull. 8, pi. \ii. ; Mass. PL Dis. p. 101, f. 17. Specking of Citrus fruits, in Australia, lias been attributed to a mould fungus /'< "iiicilliinit digitatum, causing a loss of from 2 to 50 per cent, on fruit shipped during the season. Jow a. L'.ll.s. xx\iii. p. 248. ObangE Sooty BLOTCH. Several kinds of " sooty Notch " are recorded, but it is doubtful if any of them art British. The Italian sooty blotch, MeUola Penzigii (Sacc. " Fungi Italici," figs. L182 L185), is found in South Europe, and of this Capnodium Citri l ' ibly a form. Sicilian Notch, MeUola Cilri (B, & P.), is found on Orange leaves in Sicily. Australian blotch. Capnodium cr McAlp.), occurs on loavos of Orange and Lemon in Australia. {Mass. PI. Dis p. 108.) FUNGOID PESTS OF CULTIVATED PLANTS. 16B Lemon and Orange Scab. Cladosporium Citrl (Mass.). This mould is developed on the leaves and fruit of Orange and Lemon in a manner analogous to the scab on Apples (Fnsicladium), and is very injurious to Orange trees in Florida and Louisiana. (Mass. PL Dis. p. 310.) Another and similar mould attacks Orange leaves in Italy. This is Cladosporium elegans (Penz.). The "foot-rot " of Orange and Lemon trees, in South Europe and the United States, is attributed to Fusarium Limonis (Briosi). Orange Anthracnose. Glccosporium Hendersonii (B. & Br.), PL XIV. fig. 14. This parasite of cultivated Oranges was described by Berkeley some years ago, but does not appear to be common. It occurs on the under surface of the leaves, and the pustules are scattered without forming any definite spots. The conidia, which are produced in the pustules, are oblong (12^-15 jjt long), and the mass, when extruded through the ruptured cuticle, is slightly coloured. B.&Br. Ann.N. H. No. 1702 ; Sacc. Syll. hi. 3673 ; Grevillea,\i. 126. There are seven or eight other species of Anthracnose which attack Orange leaves, especially in the South of Europe, bat they are not re- corded as British, and leaf-spots, of several genera, almost too numerous to mention, but our interest in Orange culture is comparatively small. One Italian leaf-spot, Spharclla Gibelliana (Pass.), develops asci and sporidia on living Orange leaves. Orange-leaf Anthracnose. Several species of Anthracnose have been recorded as attacking the foliage of Orange and Lemon trees in conservatories. Glmosporium Hespcridearum forms large bleached spots on the leaves, on which the pustules are gregarious and numerous. The conidia are cylindrical, straight, rounded at the ends, without guttules (11-18 x 5-6£ //.). This has been detected only in Italy. Another Italian species is Glceosporium dcprcssum, occurring also on dry spots on fading leaves, with the pustules scattered on the under sur- face. The conidia are elongated elliptical (7-8^ x2J>-4^), produced upon rather long fasciculate basidia (20-21 /j long). The Belgian species has large irregular greyish-brown spots, without definite margin, on which are seated the small whitish pustules. The conidia are ejected in flesh-coloured masses, and very minute (8 /« long). It is called Glceosporium Aurantiorum. Another Italian species (found also in France), Glceosporium inlermedhwi, has the pustules pointlike, M 2 164 FUNGOID PESTS OF CULTIVATED PLANTS. black, without forming definite spots, with long straight conidia, rounded at the ends (14-18 x 1 6 ft). 5 1 i another occurs on Orange as well as on Hoya leaves (Glccosporiiou macropus) without forming any definite spots, the long conidia (18-21 x 4-6 /x) produced on very long basidia (-IH-GO fx long). Any of these may be found in our conservatories at any time. The Olive is not sufficiently cultivated in this country to render its parasites of much interest. Fig Mould. Botrijtis chierea (Pers.), fig. 10. This mould, long regarded as a saprophyte, has been found destructive to ripe Figs, covering them with a dense felted mass of grey hyphas, and bearing a profusion of oval conidia. It apfcars to be the same species as causes the Lily disease. For other Fig parasites see " Pests of Orchard and Fruit Garden," p. 137. Journ. R.H.S. xxviii. p. xxxix and p. 29. A black mould, Ccrcosjiora BoUcana (Thiim.), has occurred on Fig leaves, and is believed to have appeared recently in Britain. Camellia Blotch. Pestalozzia Chuepini (Desm.), PI. XIV. fig. 17, This disease is far from uncommon on the leaves of Camellia under cultivation, and is so widely extended that it attacks the Tea plants in the Tea gardens of I ndia. It causes unsightly large blotches on the living leaves, which are mostly of a rounded form, but sometimes irregular through confluence of the blotche They are bleached and of a silvery-white colour on the upper rface, with a strongly defined outline, and sprinkled with the black (hits which indicate the pustules. There are no true perithecia, the sporules being produced in small cavities in the substance of the leaf, the Burrounding (-ells modified and discoloured so as to form a false ptacle. The sporules are of a remarkable kind, peculiar to the genus. In out- line the; omewhal Bpindle-shaped, being attenuated towards each end (20// Long), with three or four tran verse divisions, the apical cell colourless and conical, bearing a tuff of three or four long colourless hairs, which form a crest. The bottom cell is also colourless, and attenuated into a lone; livable h m equal in Length to that of the sporule. The intermediate cells an coloured brown, and become at Length rather opaque. 'When mature the morale an discharged fchrou'j;h the rupture of the cuticle. It is found throughout Europe and in North America, also on leaves df RhodocL , Orange, Hoya, Magnolia, Smilax, Lagerstrosmia, and Umond, hut typically on < lamellia. The only check is to colled ami hum all diseased Leaves. s,,cc. Syll iii. il L6; Cooke, Hdbk. No. 1 101 with fig. L88. FUNGOID PESTS OF CULTIVATED PLANTS. 165 Camellia Scab. Coryneum Camellia (Mass.). It must be confessed that some little mystery surrounds this parasite, which has only been detected once upon living Camellia leaves. The large blotched spots exactly resemble those which are caused in the Camellia blotch, but in that species the conidia are crowned at the apex with three or four long and spreading hairs, whilst in the present species the spores are similar in form and size, but without any crest of hairs. This may seem to be but a slight distinction, but it is the principal difference between Pestalozzia and Coryneum. It may be possible that this is an abnormal form of Pestalozzia Guepini in which the hairs are suppressed. The pustules are numerous on the whitened spots, splitting the cuticle in a linear, triangular, or stellate manner, so as to allow of the escape of the conidia. The latter are lanceolate (30xl0/i), with from two to four coloured cells in the middle, and a small triangular uncoloured apical and basal cell, supported at first on slender pedicels of the same length as the conidia. The same remarks as to prevention apply as in the case of Pestalozzia, if this is not really, as we suspect, the same species. Grevillea, xx. p. 8 (1891). Camellia Black Mould. Macrosporium Camellia (C. & M.), PI. XIV. fig. 15. Externally, and to the naked eye, this form of spotting the living leaves of Camellia so much resembles that caused by Pestalozzia Guepini that even an experienced eye can scarcely detect the difference until the microscope is employed. The silvery-white spots on the upper surface are of the same size, usually half an inch, and there is a distinct brown margin. The scattered dark points are small, but when magnified are found to consist of tufts of brown or pale olive threads piercing the cuticle. The threads are flexuous (30-40 li long), with cross divisions. Mixed with these, or supported upon them, are the club-shaped conidia, with, at first, three cross divisions, but at length double that number, with longi- tudinal divisions, like a brick wall (50-60 x 15-25 li). Downwards these conidia are attenuated into the pale olive pedicel, the whole upper part of the conidium being of a little darker olive. This may not be an injurious pest, as many of the species are sapro- phytic, and the possibility would suggest itself, whether this mould has not taken possession of a dead spot, caused by the Pestalozzia, and become established upon it. At any rate, conidia of Pestalozzia were sought diligently, and not a single one could be found. Grevillea, x'vii. 42 ; Sacc. Syll. x. 7837. Gardenia Canker. PL XIV. fig. 1G. Tumours are formed on the stems, at the base, just above the ground, or on branches near a fork, on G/irdmia and also on Camellia. They 166 FUNGOID PESTS OF CULTIVATED PLANTS. resemble other cankers, and appear to be the result of local irritation. The bark around, which was at first, perhaps, a wound, swells, becomes corky, and of a rusty-brown, covering a patch an inch or more long. When the centre of the tumour is bare, the woody tissue is seen to be dead, and occupied by black dots, which are the thin receptacles of an immersed I'h ma, with minute narrowly elliptical conidia (7x2 fx). This is not the cause of canker, but a sequence. Sometimes several scars are coniluent at the bottom of stems, and are swollen in a gouty manner by the corky transmutation of the surrounding cell. Hoya Leaf- spot. Phyllosticta Bollcana (Sacc), PI. XIV. fig. 19. Forming spots on the living leaves of Hoya canwsa, which are bleached to a greyish-white, with an irregular brown margin, forming a striking contrast to the bright green of the leaf. The receptacles are scattered over the spot like minute black dots to the naked eye, containing the small elliptical sporules, which are just tinged with grey (4-5 x 2-2!, p.). It is doubtful whether the minute fungi of this genus, which forms spots on living leaves, are to any considerable extent injurious to the plant. They may become so by disfiguring the foliage, especially if they spread themselves, but they are certainly incapable of inflicting such injury as that caused by the various kinds of Anthracnose. Their life- history is at present much involved in mystery. Probably, should any of them prove troublesome, it would be well to submit the plants to treatment with one of the copper solutions. Sacc. Syll. iii. 70 ; Grevillea, xiv. 39. Another leaf-spot (Septoria Iloyce) forms various white spots on Hoya- leaves, girt by a brownish ring, sporules threadlike (20-25 x 1-H p) or a little club-shaped. In botanic gardens in Italy. Hoya Anthracnose. • roaporium ajjinc (Sacc), PI. XIV. fig. 18. Thifi jpot has recently made its appearance in hot-houses at Glasgow, and may soon travel southwards. It was previously known in Italy; it belongs t" B genus which is eminently destructive, and includes many pi is. 'I'h. pol 00 the Lea 1 variable, both as to size and form, becom- ■ bleached or whitened, having little pustules on the surface. These pustules are scattered, and consist of small discoloured cells, without any true or distincl outer covering or receptacle, nestling beneath the blackened cuticle. The pustules appear chiefly on the upper surface. At length an Irregular opening Is made, and the conidia ooze out in the form of a tendril. They are cylindrically oblong, rounded at the ends, COlourleBS, and Spring at lir-t from the cushion-like base of the pustule, borne on short delicate hasidia. Conidia of moderate size for the genus (l 1 -20 < i-r. ,ti). PL. XV. PESTS OF CONSERVATORY. FUNGOID PESTS OF CULTIVATED PLANTS. 167 The parasite occurred on leaves of Hoya and on JEscliynanthus. Apparently the same species has also occurred on leaves of Orchids at Glasgow. Wr can only advise strict burning of all diseased leaves. Sacc. Syll. iii. 3707 ; Grevillea, xix. 42. Two other species of Anthracnose are recorded on Hoya, in Italy, under the names of Glceosporittm sphcerelloid.es and Glmosporium macropus. Tea and Coffee Pests. The fungoid pests of Tea and Coffee shrubs are not of much interest to the home horticulturist, although of considerable importance in the tropics, the Ceylon Coffee disease especially, Hemileia vastatrix (Berk.), having caused immense damage in the plantations, not only of Ceylon, but in Southern India and in tropical South America. So also has the Coffee leaf-rot, Pellicularia Koleroga (Cooke), in Southern India. The Tea shrub is liable to the attacks of Pestalozzia Guepini, which is described above. Gard. Chron. Oct. 25, 1879, fig. 87. Azalea Leaf-eot. Pestalozzia longiseta (Sacc). This species was first found in Italy on living leaves of a species of Bubus, but in this country it has been found on Azalea leaves. The spots are rufous, margined by a black line, on which are seated the point- like pustules, which are themselves black, covered some time by the cuticle. The conidia are almost fusiform, pointed towards each end (20 x 8 fi), divided by four transverse septa. The three central cells are coloured dark brown, the two extreme cells small and colourless. From the upper cell spring three very long hairlike processes (30-40 xl/i). The lower cell is attached to a slender hyaline pedicel. Like Anthracnose, this is a deeply seated endophytal disease, and all that can be done is to prevent its spreading. Sacc. Syll. iii. 4115 ; Grevillea, xv. p. 19. Another leaf -spot, of an ordinary kind {Septoria Azalea), has been recorded in Italy, and is just of the kind that is likely to spread. A rust on Azalea has been known in North America ( Uredo Azalea) for very many years, but does not appear to have done much mischief. Jasmin Chain Mould. Chromosporium pactolinum (Cooke), PI. XV. fig. 22. First described under the name of Oidium pactolinum, when it was found on living leaves of Jasminum Sambac, forming a thin stratum, as if sprinkled with gold-dust or chrome powder. The threads, if any, were not to be detected, the powder consisting of the nearly globose conidia, 168 FUNGOID TESTS OF CULTIVATED PLANTS. attached to each other in chains of from six to ten cells. Whilst remain- ing attached, the ends'of the conidia are flattened at the point of junction, but when free they acquire a globose form (10 /.i diam.), with a thin hyaline membrane, but with granular golden-yellow cell-contents. At present this has only been recorded in Britain, and is certainly epiphytal, probably not at all injurious to the plant: at any rate it is very curious. Grevillea, xii. 98; Sacc. Syll. vi. p. 633, x. p. 511. Two or three kinds of leaf-spot have been caused upon Jasmin-leaves by imperfect fungi, but none of these have been recorded as British. Passion-flower Black Mould. Zygosporium oschcoides (Mont.), PI. XV. lig. 23. This minute black mould was first discovered in Cuba, growing on dead leaves, and was only regarded as a saprophyte, but recently it has been recorded on leaves of Passijlvra quadrangular is, seemingly under the impression that it was a parasite, and a new species, under the name of Cladotrichum Passificrce (Pirn.). The fertile threads are erect, septate (70 x 3 /<), sooty-brown, inflated and paler at the apex, at the base emitting a semilunar sporophore. Conidia, oval or globose, produced singly or in pairs at the apex of the sporophores (5/u diam. or 12 ^ long). The peculiarity is that the hyaline conidia are borne at the end of curved club-shaped branches, which is sufficient to identify the species. This same mould has been found in Cuba and elsewhere on Screwpines and Palms. /. ( )i;i inn lii.AcK Moild. 01 Hum Orchidearum (C. & M.), PL XV. fig. k 29. There Deed he no alarm amongst Orchid-growers respecting this new form of para ite which falls upon decaying Leaves, since we are convinced that it only in.: appearance on dead or diseased tissue. The threads are in tufts which SOI in to protrude through the stomata, and are short, here and there branched and septate, hut slender and ilexiious, and of b pale olive colour. The spores or conidia are borne at ih(' tips of the branches, and are mostly elliptical, with a cross division in tin oentri forming two cells (17 18x6 <"> /,) of a pale olive colour. The conidia an \ i iry variable in this genus, both in si/.e and form, some being found without a division and others with two or three, but in the present Instance we bav< oba rved uone with more than one division. Qcurd. Chron. Oct. 11, 1890, fig. H2 ; Sacc. Syll. x. 7500. FUNGOID PESTS OF CULTIVATED PLANTS. 173 Vanilla Antheacnose. Gloiospor'mm Vanilla (C. & M.). Hainesia Vanilla (Mass.), PI. XV. fig. 29*. The Vanilla disease described by G. Massee has evidently no con- nection with Bidgood's Anthracnose, nor has it, perhaps, much interest for the English cultivator, but concerns more intimately Vanilla-growing countries. This species has been found to develop into a higher con- dition systematically, where it is known as Calospora Vanilla, but its destructive stage is the Anthracnose. It appears on the leaves of Vanilla in the Mauritius, Seychelles, and Reunion Islands, as well as New Granada. The pustules are small, on either surface, covered by the blackened cuticle. The conidia are elongated, elliptical, and colourless (14-16 x6-7 /j.). On account of some slight technical distinction, of very doubtful value, the name has recently been changed to Hainesia Vanilla, but the name is of very slight importance. Sacc. Syll. x. 6815 ; Grcvillea, xv. p. 18 ; Kew Bulletin, 1892, No. 65, plate ; Mass. PL Dis. pp. 113, 368. Bidgood's Orchid Anthracnose. Glaosporium Bidgoodii (Cooke), PI. XV. fig. 30. This disease has only been determined during the latter part of the year (1901), although its effects have been recognised for the past six years. The leaves attacked have been those of Odontoglossum. The tips of the leaves become yellow, but the spots appear to start anywhere, and now the black shining pustules have been found upon the spots, which the late Mr. Bidgood correctly indicated as those of a species of Gloeosporium, but as he did not describe it hitherto, it was but courtesy to associate it with his name, as he devoted much time and energy to its investigation. The pustules are rather large, and covered by the blackened cuticle, at length ruptured for the escape of the conidia. The stroma upon which the conidia are produced is also blackened, but the conidiophores become hyaline above, bearing the narrowly elliptic conidia (18 20 x 4 /<), which have two nuclei. No direct evidence has yet' been furnished that the conidia become uniseptate, although one of the microphotographs taken might give that impression. Journ. B.H.S. xxvi. 1901, pp. cxxxix and cxli, vol. xxviii. p. 262 ; Trans. Brit. Myc. Soc. 1903, p. 15. American Orchid Anthracnose. Glceosporvum cinctum (B. & C), PL XV. fig. 81. This species occurred on cultivated Orchids in Massachusetts, and was described by Berkeley. The pustules arc minute and gregarious, covered and circled by the blackened epidermis, so as to appear like little black rings. The conidia are oblong and obtuse at both ends, sometimes curved, granular within (10-15 x 2 J, -3 /<). The species of Orchid has not been recorded. 174 FUNGOID PESTS OF CULTIVATED PLANTS. It is not clear that this species has been found in this country, since the suspicion that the species found on Orchids at Glasgow was the same is without good foundation, the size of the sporules being different, and, as far as can be ascertained, the pustules in the above species are not produced upon bleached spots. • Neither, again, can the more recent Orchid Anthracnose be referred to this species, which we have called here Glaiosporium Bidgoodii, since the external appearance and fruiting appear to be different. Sacc. Syll. iii. 8765 ; Joimi. B.H.S. xxvi. 1902, p. 729, fig. 305. Other Orchid Anthracnose. As this seems the most fatal source of Orchid disease, we may enumerate the known species of Anthracnose found on Orchids. Malagasy Orchid Anthracnose. Glccospoi ium pallidum (Karst.). This species was found on the leaves of Orchids from Madagascar cultivated in France. The pustules are pallid, and not blackened as is often the case, and the conidia oblong, straight, and obtuse at the ends (10-16 x 3-6 /<)• Sacc. Syll. x. 6816. Mexican Orchid Anthracnose. GUeospoHum Orchidearum (Karst.). In this instance the pustules are covered with the blackened cuticle, which is split longitudinally to allow the conidia to escape. Perhaps the most distinctive feature is in the form of the conidia, which are elongated fusiform, or unequal-sided (20-25 x 5-7 n). Sacc. Syll. x. 6*17. Cattleya Disease. A species of GlaospoHuni has occurred around Faris on leaves of Cattleya. Jonrn. I;. U.S. xxix. p. 764. Oncidh m Anthracnose. Glososporivm Oncidii (Oud.). This species occurred on the leaves of Oncidvu/m in the Botanical ( hardens at Amsterdam. In this case the pu dules arc round and brownish- .. perforated in the centre Eor the escape of the conidia, which are oblong or pear baped (1 I 17 x 4^-6 /») and are ejected in a rosy mass al the orifice of the pustule. Sacc. Syll \\. 8668. ()l;< MID HeMILE] \. Hemileia americana (Mass.). A rust has made its appearance on leaves of One/ilium, imported from Guatemala into this country. It is kindred to the dreadful FUNGOID PESTS OF CULTIVATED PLANTS. 175 Coffee disease, which has wrought such havoc in Ceylon and other places. Gard. Chron. Aug. 19, 1905, p. 153, fig. 53. Screw Pixe Black Anxhkacxose. Melanconium Pandani (Lev.). Screw Pines under cultivation are liable to attack from a fungus which settles itself irrespectively upon the trunk, aerial roots, and adven- titious branches, where it forms small black pustules, which are sometimes so numerous as to blacken the parts attacked. The productive cells are concealed beneath the cuticle, but there is no true perithecium or recep- tacle, and the conidia are formed upon a kind of cushion, or stroma, supported at first on rather long branched stalks. They are elliptical or oblong, either straight or slightly curved, often with two nuclei, but variable in size (5-9 x 3-4 fi), pale olive, oozing out, when mature, either in black tendrils or irregular inky masses. This species was made known in 1845, but has not been much heard of since. It is allied to the species of Anthracnose, but with coloured conidia. Another fungus, bearing the sporidia contained in asci (Nectria Pandani), has also been found on Screw Pine, of which it has been sug- gested that the above is a condition ; but we think that the suggestion is of very little value, as there is no precedent for such an association. Ann. Sci. Nat. Bot. 1845, p. 66 ; Mass. PL Dis. pp. 293, 431 ; Sacc. Syll. iii. 3985. Palm-leaf Pustule. Graphiola Phdsnicis (Poit.), PI. XV. fig. 32. This peculiar kind of fungus is found on the living or fading fronds of Palms in conservatories, in Britain and most other parts of Europe, in North America, parts of South America, Ceylon, India, and Algeria. The pustules appear like hard, black, superficial, round excrescences upon the leaves, being developed beneath the cuticle, but soon erumpent (1-1^ mm. diam.). They possess an outer horny coat and a thinner inner coating, which is filled with fertile threads, and numerous rather small (3-6 /.<) globose yellowish uredospores, with a hyaline membrane. When the spores are dispersed the threads remain for some time in a tuft within the remains of the black outer coat, looking scarcely like either a rust or a smut. Sacc. Syll. vii. 1915 ; Cooke, Hdbk. No. 1637; Tubeuf, Dis. p. 326; Cooke, Hdbk. Austr. Fungi, t. 28, f. 260. The black mould Zygosporium oscJieoides has also been found on Screw Pine and the foliage of palms in tropical countries. Palm-leaf Black Mould. Heterosporium minutulum (C. & M.), PL XV. fig. 33. This mould is of the same nature as one which is very destructive to Carnations, and occurs on the leaves of Palms, in this instance on 176 FUNGOID PESTS OF CULTIVATED PLANTS. Chamcerops hit mil is. It forms dark olive velvety patches of variable size and form, sometimes considerable in extent, with a creeping mycelium. The threads are mostly collected in tufts, and are rather short, flexuous, and sparingly septate, of a pale olive colour. Conidia with one or two septa, elliptical, rounded at the ends, but not constricted at the joints, pale olive (1G-20 x 6-8 /a), and externally rough, as in other species of the genus. This is also at present only recorded for Britain, but it belongs to such a persistent group of parasites that it will probably be heard of again. Grevillea, xvi. 11 ; Sacc. Syll. x. 7707. Palm Leaf-spot. Exosporium Palmivorum (Sacc). Another palm leaf disease has made its appearance in France on Phoenix canariensis and other species, and is known also in the United States. The conidia have from 8 to 10 septa, and measure : 75-95 x 7-9 p. It has appeared also in Eastern Europe. Sacc. Syll. xvi. p. HOG; Btcll. Soc. Myc. clc Fr. xxi. fasc. 3, p. 173, figs. 3, 4. A small dot-like fungus, Phoma Kentice (Cooke), has been found flourishing on the dead tips of the fronds of Kentia, under cultivation, with sporules 8-10x4 fi. It is doubtless only a saprophyte. Other species, assumed to be parasitic, have been described as occurring on Kentia in Algeria, as Pl&ospora Kcntice (Maubl.), Ascochyta Kcntice (M.), and Stagonospora Kentia (Maubl.). All of them on living leaves. I S<>c. Mi/col. cle France, xix. fasc. 3, p. 293.) Bamboo Mould. Oosponi in equal is (C. & M.). This is a thinly effused white mould, found on the culms of growing Bamboos, under certain conditions of weakness. It spreads broadly but thinly like a glaucous bloom, of a pale grey colour. The conidia are unequal in size and form, from globose to elliptical, 1 1 i i i i * d together, end to end, in short curved and either simple or branched threads, colourless, and when globose 5 /a diam., attaining to double that Length, with the Bame diameter. The specific name lias since been changed to Oospora Cookei by Sacc: ii-' I o on accounl of the prior adoption of incequalis. It is scarcely probable thai it would resist moderate spraying. Grevillea, xvi. p. 10; Sacc. Syll. x. 70">7. FISTS OF THE ORNAMENTAL SHRUBBERY. Notwithstanding the entirely artificial character of such subdivision, it appears to be the mosl practical method to separate ornamental shrubs into the two groups of evergreen and deciduous, independently of anomalies which may here and there obtrude themselves. The same parasite very rarely attacks both coriaceous- and tender-leaved plants. PESTS OF ORNAMENTAL SHRUBBERY. FUNGOID PESTS OF CULTIVATED PLANTS. 177 CORIACEOUS-LEAVED SHRUBS, or Evergreens, are represented by the following. Rhododendron Galls. Exobasidmm Rhododendri (Cram.), PL XVI. fig. 1. The gall-like swellings on the leaves of Rhododendron ferrugincunv and R. hirsutum, and possibly of other species, are sufficiently striking not to escape the notice of even a casual observer. They vary in size from that of a pea to that of a marble, and are often found several of them together in a cluster. At first they are of a pale yellowish-green colour, then they acquire a reddish or roseate tint, especially on the sunny side. When fully and properly mature, the surface is covered with a delicate frosty bloom, like the bloom on a plum. It is in this "bloom " that the fungus exhibits itself, for the mycelium is concealed within the tissues of the gall. The fruiting consists in the development of erect stout spore-bearers, called basidia, which resemble the same organs on the gills of an Agaric. The apices of these basidia carry a definite number, usually four, apicules, each of which supports a spore, or basidiospore. These spores are colourless, elliptical (8-10 x 6-7//), and readily fall away. These galls differ essentially from the Peach blister in the spores being naked and exposed, not enclosed in asci, and in being produced upon the outer and convex, not on the inner and concave surface. Known also in France and Germany. Diseased leaves should be burnt as soon as the fungus shows itself, and before spores are produced. Sacc. Syll. Hym. ii. 7797 ; Gard. Chron. 1879, p. 119, 182; Mass. PL Dis. 168, 398, fig. Similar galls are produced on Bay-Laurel. Rhododendron Leaf-spots. Several kinds of leaf-spot are known on species of Rhododendron, but have never caused anxiety, as they simply disfigure the leaves. Some of these may be enumerated. Phyllosticta Saccardoi, forming orbicular spots with a tawny margin, and small sporules (4x1 //), in France and Portugal. Phyllosticta rhododendricola, with large irregular grey spots having a brown margin, and larger sporules (8-10 x3fi), in France. Phyllosticta Rhododendri, with rusty-brown spots, chiefly marginal, and the sporules oozing out in flesh-coloured tendrils. Found in Belgium and Britain. Phyllosticta maxima, with large brown spots with dark margin, and rather large sporules (10-12 x 6-8/1), confined to North America ; with Septoria Rhododendri, having orbicular pallid spots girt by a dark purple margin, and thread-like sporules (40 /i long), and a similar Sevtoria solitaria, with sporidia half as long, on Rhododendron occi- dentale in California. N 17s FUNGOID PESTS OF CULTIVATED PLANTS. There are also two species of anthracnose known. Glososporium Rhododendri, with large irregular spots, which are zoned, and have a black margin, the sporules 15-20x4-5//, found in Italy, but not certainly British. And eosporium succineum, with sporules about the same size, but globose and yellowish. Altogether a doubtful Siberian species. Rhododendron Brand. Puccinia Rhododendri (FckL). This brand has been found on the under surface of the leaves of Rhododendron fcrrugineum in the Tyrol, but there is no record of it else- where. The teleutospores are ovate, slightly constricted at the middle (26 x 18 /i), brown. Sacc. Syll. vii. 2474. A rust on the leaves of Rhododendron fcrrugineum, dauricum, and hirsutum, distinct from the above, has been found in Italy, France, Germany, and Asiatic Siberia. It is known as Chrysomyxa Rhododendri 1 1 >('.). Teleutospores (10-14 /i broad) obtusely rounded above. Uredo- spores warted, orange-yellow (17-28x15-22//). e. Syll. vii. 2660. Leather-leaved Bristle SroRE. Pestalozzia Guepini (Desm.), PI. XIV. fig. 17. This disease attacks numerous plants with coriaceous leaves, besides Rhododendrons, such as Iloya, Camellia, Citrus, and Magnolia. Greyish spots are formed on the leaves, often near the apex, usually with a distinct and perhaps elevated margin. The pustules are scattered like little black specks over the spots. The conidia are large, produced within the pustules, and extruded when mature. They are somewhat narrowly elliptical (20 25 /x long), attenuated at each end, and divided by three or four transverse septa; the end cells smallest, conical, and colourless, : the Intervening cells brown. The apical cell furnished with three or four long divergent hairs, as long as the conidia, the basal cell attached to a colourless footstalk or peduncle. Diseased li hould be collected and burnt before the sporules are matured. Sacc. Syll. iv. 11 16; Cooke, Hdbk. No. 1 101 ; Mass. PL Dis. p. 432. Oleandeb Leaf-spots. <>n the Continent, where Neri/u/m Oleander is cultivated much more Ively than in this country, its pests and parasites are of Ear more interest, whereas we have no record of B single occurrence. Phyllosticta Nerii has rather Large iporules (15-lHx5- (>/a). .1 cochyta Oleandri, with septate sporules rather smaller (11-15x2 Septoria la has short thread-like sporules, and so also has Septoria oleandrina, both of which are known in [talj ; and Hhahdospora FUNGOID PESTS OF CULTIVATED PLANTS. 179 Olcandri which is parasitic on the twigs, and not upon the leaves, in Algeria. The latter is apparently the Septoria Olcandri of Montagne. Akbutus Leaf-spot. Phyllosticta Arbuti (Desm.), PI. XVI. fig. 2. The parasites of the Strawberry tree are, for the most part, confined to the ordinary leaf-spots of small importance, and of these the most common is the above-named, which forms small dingy spots scattered over the leaves. The receptacles are very small and sprinkled like little dots over the upper surface of the spots, sometimes densely clustered together. The sporules are also very minute, ovoid, and colourless (5 x 3 p), often exhibit- ing two small nuclei. The attacked leaves are in most instances at first fading. This has been recognised in France and in Britain. To pick off and burn infected leaves is to help preventing the spread of the parasite. Sacc. Syll. iii. 118 ; Grevillea, xiii. 72. Another species has been detected in Portugal and Algiers (Phyllosticta microsticta Dur.) with small spots which soon become white, with a distinct dark brown margin. The sporules are even smaller than in the above. Akbutus Purple Spot. Septoria Uncdonis (Rob.), PI. XVI. fig. 3. This is apparently the most common of the Arbutus parasites, and causes small whitish spots upon the leaves, which are circumscribed by a broad purple margin. The receptacles are scattered over the upper surface of the spots, and the sporules are elongated and thread-like (25 x H p), but without indication of septation. It is recorded for France, Portugal, Italy, and Austria, as well as in Britain. Sacc. Syll. iii. 2061, x. G282 ; Cooke, Hdbk. No. 1322. A form of leaf-spot has been found in Italy, supposed to be a variety of the above, although that seems to be doubtful, since the sporules are twice as long and distinctly septate (50-80 /z long). Another leaf-spot (Septoria Arbuti) has been found in Italy, which much more resembles the above type than the assumed variety, since the sporules are almost the same. Akbutus Tuft Mould. Cercospora Molleriana (Wint). The only mould which is recorded as attacking the foliage of the Straw- berry tree has occurred in Portugal, but its appearance in any other put of Europe is open to doubt. The spots are normally circular, but often marginal, and pallid grey, with a distinct margin. The mould appears in n 2 180 FUNGOID PESTS OF CULTIVATED PLANTS. tufts upon the spots, with quite short threads, hut the conidia are elongated, slightly curved and attenuated upwards, divided transversely into numerous cells (95 x 3| /j). Both threads and conidia are tinged olive. Sacc. Syll iv. 2269. Magnolia Leaf-spot. PJiyllosticta Cookei (Sacc), PI. XVI. fig. 4. As might be anticipated, the fungus attacks on Magnolia are far more numerous in America than in England, and even those which we do recognise are but seldom to be met with. The one above named, when first found, was called PJiyllosticta Magnolia', but that name was after- wards found to have been previously appropriated. The pale bleached spots on the leaves are rather large and without any definite margin. The minute receptacles are scattered over the spots, on the upper surface ; and the sporules are narrowly elliptical (8-12 x 3-4| /u) and uncoloured. There is no probability of this ever becoming a troublesome pest in this country on the leaves of Magnolia grandiflora, on which it was first discovered. Grevillea, ix. 94, xiii. 72 ; Sacc. Syll. iii. 130 bis. The older PJiyllosticta Magnolia is very similar in external appear- ance, and has occurred in Italy, but the sporules are not one half as large (4xH-2/.). Phyllosticta glanca on leaves of Magnolia glauca is exclusively American. Spots caused by species of Ascockyta and Septoria are also known, but not hitherto as British. EVERGBEEN LEAF-SPOTS. It is somewhat fortunate that the Evergreen shrubs, which are so commonly and extensively cultivated in this country, are remarkably free from leaf-spotting fungi. Aucuba japonica can boast of several in Continental Europe, but not a single British record. Prunus lusitanica is just as fortunate, or it has not been found out. I 'nun's Liiuroccrasus has its fungi on fallen leaves, but not upon the living, except in other parts of Europe. Laurus nobilis sometimes exhibits spotted leaves, but hitherto there is no evidence that they result from the incursions of parasitic fungi, else- where than in Italy or Portugal. {Phyllosticta Lauri, Sacc. 84.) Ih.r A . p. 201 ; Cooke, lldbk. No. 1514; Sow. I'iiu. t. 189. hv Leaf-spot. Phyllosticta hedericola (Dm-. A- Mont, f.j, I'l. \\'l. fig. 10. This spot has been Known for many years on [vy Leaves and occurs on the upper surface, causing round bleached spots with a rather broad brownish margin. The small receptacles are dotted over these spots, and i nclose the oblong hyaline sporules (6 x 2£ p). Although first recognised in Algeria, it has since been recorded iu Britain, France, Italy, and Austria. Sacc. Syll. iii. 10d ; (Ircrillca, xiii. 71. Two other species of the same genus of leaf-parasites have occurred on Ivy leaves in Europe : Phyllosticta Hedtra on large brown spots, with » 2 i 'S* PESTS OF ORNAMENTAL SHRUBBERY. FUNGOID PESTS OF CULTIVATED PLANTS. 183 smaller sporules (4x1 /i), in France and Belgium, and Phyllosticta concentrica with broad pallid spots, on which the receptacles are disposed concentrically, with sporules which are nearly globose (10 x 8-9 /i), only at present recognised in Italy. Ivy Brown Spot. Septoria insularis (B. & Br.), PI. XVI. fig. 11. This parasite was first recognised by Berkeley as causing large brown spots on languid Ivy leaves in Britain, sometimes occupying a large portion of the leaf. The receptacles are scattered over the spots, raising and afterwards splitting the cuticle. The sporules are long and thread- like, slightly curved, but without division (38 \i long). Berk. Ann. N. H. No. 747, 1. 15, f. 8 ; Sacc. Syll. iii. 2646 ; Grevillea, xiv. 76 ; Cooke, Hdbk. No. 1308. Ivy Ringed Spot. Septoria Hedera (Desm.), PL XVI. fig. 12. This is a much more common species than the above, and forms smaller, almost circular, bleached spots, encircled by a broad purple margin. The receptacles are seated on the upper surface, and the sporules are similarly thread-like (30-40 x 1-2 fi), the difference being chiefly in the character of the spots. It has been known in Britain, France, Belgium, Italy, and Germany. Sacc. Syll. iii. 2644 ; Grevillea, xiii. 76 ; Cooke, Hdbk. No. 1316. Ivy Leaf Anthbacnose. Glceosporium paradoxum (De Not.), PI. XVII. fig. 13. Of the two species of European anthracnose on Ivy, one has been reported to have been found in Britain. This was apparently first observed in Italy, and occurs on both surfaces of the leaves, without forming any definite spots. The pustules are honey-coloured and flattened, covered by the cuticle. When mature the conidia escape by rupture of the cuticle (8 x 5-6 /u), produced in clusters, each supported by a colourless pedicel, which is nearly double the length of the conidia. This is reported to be an early and imperfect stage of an asci-bearing fungus, which appears on the dead leaves after they have fallen The species is also known in France, Belgium, Germany, Portugal, and Italy. Sacc. Syll. iii. 3697 ; Cooke, Hdbk. No. 1407, note. Another species, which occurs on Ivy, has brownish spots with larger conidia [Glozosporium Helicis), and has been found in France and Holland. Myrtle Leaf- spot. Phyllosticta nuptialis (Thiim.), PI. XVII. fig. 14. The only parasite on Myrtle which we have yet encountered in this country has been the occurrence, on one or two rare occasions, of the above species. The spots are somewhat rounded and bleached, either 184 FUNGOID PESTS OF CULTIVATED PLANTS. white or of a pale ochre, with a broad violet margin showing brown on the under surface. The receptacles are scattered over the upper face of the spots and enclose the very minute subglobose sporules (2-2^ x H /*)• This species was first detected in Portugal. . Syll. iii. 32. A Mack mould (Ccrcospora Myrti) has been detected upon leaves under cultivation at Stockholm, but this seems to be the only record. Phillyrea Leaf-spot. Phyllosticta Phillyrea} (Sacc), PI. XVII. fig. 15. This spot is found on the leaves of Phillyrea media and Phillyrea latifolia, affecting the upper surface, and producing variedly shaped spots, of an ochraceous-grey colour, with a reddish margin. The receptacles are scattered over the spots, and enclose the oblong, almost spindle-shaped sporules (6-7 x 3 fx), each containing two minute guttules. It has been recorded in France and Italy, as well as Britain, and should be treated as other leaf-spots. Sacc. Syll. iii. 113 ; Grevillca, xiii. 72. Another species is known in Portugal {Phyllosticta vhillyrina), occurring on leaves of Phillyrea ohliqua, but with smaller sporules (4-5x2-2!; /,). Phillyrea Bust. Urcdo Phillyrece (Cooke), PI. XVII. fig. 1G. This uredo is found sometimes rather plentifully on shrubs of Phillyrea media, not only in P>ritain but also in Germany, Italy, and in Algeria. The pustules are round, yellow, and either solitary or collected together, arranged in rings. At first covered by the cuticle, but at length exposed. Uredospores globose, pear-shaped, or elliptical, delicately -pinulose or almost smooth, orange (17-28x12-10 /w), without definite pedicels, and with a thick hyaline outer coating. Sacc. Syll. vii. :J090; Plowr. lint. Ured. 268. PHILL"5 ki:\ (i.isi u; CUPS. . Kcidiit.ni Pit illy i ' ><■ | I >C). These cluster-cups, which appear to be independent of uredo or teleutospore, occur on the leaves and twigs of Phillyrea media and latifolia, BOmetimes Contorting and deforming the latter. The cups are clusten d iu roundish patch) s on the Leaves, for the mosl part crowded, with tin margins nearly entire. /Kcidinspores very variable in form, being sometimes globose, or elliptical, or pear-shaped (18-85 X 14-20 //), externally warted, orange-yellow. On the stems the dusters are more elongated, thickened, and distorted. Known in France, Germany, ami Italy. Sacc Syll. vii. 2852. FUNGOID PESTS OF CULTIVATED PLANTS. 185 CoTONEASTER SPOT. Phyllosticta sanguined (Desm.), PL XVII. fig. 17. This species, which is usually found on the dead leaves of the Bird Cherry, has occurred in this country on the living leaves of Cotoneaster frigida. The spots are roundish and brown, girt by a darker line, out- side which the tissue is stained of a blood red. The receptacles are scattered over the spots, and are black, point-like, and shining. The sporules are ovate, with two nuclei (8 /x long), and uncoloured. Known in France and Britain. Sacc. Syll. iii. 14 ; Grevillea, xiii. 71. Butcher's Broom Spot. Phyllosticta ruscicola (Dur. & Mont, f.), PI. XVII. fig. 18. This pest occurs on the phyllodes of the Butcher's Broom, Ruscus aculeatus, and other species. The spots are roundish or indistinct, whitish, with a brown border, and the perithecia, which are seated upon these spots, are at first covered. The sporules are oblong and colourless (7-8 XH yLt). Probably this is an imperfect condition of an ascomycete, which is developed on the dead phyllodes. It is not only common in Britain, but is known also in France, Belgium, Portugal, Austria, and Italy. Sacc. Syll. iii. 319 ; Cooke, Hdbk. No. 1346. As the phyllodes are persistent, this may be regarded for our purposes as an evergreen shrub. Mahonia Leaf-spot. Phyllosticta Mahonia (Sacc. k Speg. f.), PI. XVII. fig. 19. Mahonia leaves are rather given to discoloration and sometimes to spotting, but in this instance no definite spots are formed, and the receptacles are scattered over the surface. In British specimens the leaves were still living and adhering to the plant, but the receptacles were rather larger than usual, containing broadly elliptical sporules (4-6 x3-4/i). It has been found also in France and Italy. Sacc. Syll. iii. 131 ; Grevillea, xiii. 72. Another spot is known to occur on the leaves of Mahonia japonica, in which large bleached spots occur with a brownish margin. The sporules are scarcely different in size (4-4^ x2^-8 /<), but the spotting is quite distinct. It has been found at present only in Portugal. The ordinary leaf-spots (Phyllosticta lierbcridis and Septoria Uei- beridis) on leaves of the common Berberry have not yet been observed in Britain. Grevillea, xiii. 72. JEcidium Berbcridis sometimes occurs on the leaves and berries of Mahonia. See Smith, Field Crojis, fig. 87. 186 FUNGOID PESTS OF CULTIVATED PLANTS. DECIDUOUS-LEAVED SHRUBS here enumerated are succeeded by a small subsection, which includes coniferous and allied shrubs, to which, perhaps, should have been added some of those hereafter included with Conifera, under the " Pests of Forest Trees." Berberry White Mould. Ovularia Berberidis (Cooke), PL XVII. fig. 20. This mould occurs on the fading leaves of Berber is asiatica, forming greyish-white patches, reminding one of Oidium. The short, slender, unbranched threads are collected in tufts, bearing about their apices the elliptical, uncoloured conidia (15-18x8-9 p). These moulds are susceptible to the influence of fungicides, should they prove troublesome. Sacc. Syll. x. 716 ; Grcvillca, xvi. 62, xiii. 98. Berberry Anthracnose. Glceosporium Berberidis (Cooke), PI. XVII. fig. 21. This anthracnose on the leaves of Berberis asiatica was first observed in this country in 1881. The spots are on the upper surface, and are broad, somewhat circular, brown, with a reddish margin. The pustules are numerous upon the spots, convex, at length splitting at the apex to liberate the conidia, which are ovoid and colourless, comparatively small (5 x 8 //). Sacc. Syll. x. 6756 ; Grevillca, xiii. 98. Purple Berberry Spot. 1'hijllosticta asiatica (Cooke). This spot was found on the leaves of Berberis asiatica about the sume time as the anthracnose, which to some extent it resembles exter- nally. The spots are circular or irregular, and pale brown, with a broad purplish margin, which becomes crimson as it passes into the leaf. The receptacles are seated on the upper surface upon the spots, and are very minute ami point-like. Sporules very small, hyaline (4 x H /<). Sacc. Syll. \. 4865 ; Orevillea, xiii. 91. Bebbebbt Leaf Mildew. Microsphcera Berberidis (DC), PI. XVII. fig. 22. The Berberry Mildew is a common pest of Berberis vulgaris, and partakes of the character of the mildew of the Gooseberry, the (