76 SUMMARY OF CURRENT RESEARCHES RELATING TO 



at in a series of statements. He maintains that sclerotia are capable of 

 germination after being kept for two years : that a number of .sclerotia 

 in the open do not succeed in germinating the first year, but that they 

 also germinate in the second year under favourable conditions. He 

 found that even when mouldy or broken in pieces they produced the 

 Peziza form, and it was immaterial Avhether they were kept dry during 

 the intervening season, or were kept moist as had been thought necessary. 

 The time of germination varied during the first half of May. 



Erysiphe graminis.* — E. M. Reed's infection experiments with 

 Erysijyhe (jraminis confirm the findings of previous workers in this field 

 as to the existence of biologiad species. He found that the form on 

 rye would infect no other grass, tliat the same fungus on Poa pra- 

 tensis was equally specialised, though in certain conditions it could be 

 transferred to P. nemnralis, P. trivialis, and P. compressa. Other in- 

 fections only confirmed the existence of biologictd species in the mildew 

 of grasses. 



Yeasts and Cysts in GlcEOsporium.t— Viala and Pacottet publish 

 in more detail work already communicated on this subject. They add 

 an account of their researches on Ascochyta Pisi, a somewhat similar 

 fungus. During ten months of culture they got no trace of poly- 

 morphism, neither yeasts nor cysts, showing thus a considerable divei'- 

 gence from (Theosjioriimi. A note is added on the installation of the 

 Research Station for vine diseases. 



Origin of Yeasts. | — In discussing Viala and Pacottet's recent work 

 on the inclusion of yeasts in the life cycle of the higher fungi, A. 

 Guillermond points out that the fertilisation process observed before the 

 formation of endospores rather tends to show that all such spores are 

 from asci with a sexual origin ; that the endosporic sacs described by 

 these writers probably do not belong to Mangmia and Gnomonia as they 

 supposed. 



Polymorphism of Colletotrichum.§ — B. Namyslowski experimented 

 with a species that grew on the leaves of Poa trivialis. In artificial 

 cultures the conidia germinated and formed only chlamydospores. The 

 fungus mycelium in a culture produced both chlamydospores and the 

 typical conidiophores and conidia of Golletotrichum. Reinfection of Poa 

 with these conidia was without result. 



Hyphomycetes.|| — G. Lindau finishes the Arthrine(e with the three 

 genera Goniosporium, Gonatobotryum and Arthrinium begun in a previous 

 fascicle. The Trichosporieae and Monotosporeae are also worked through. 



* Trans. Wis. Acad. Sci. Arts and Letters, xv. (1905) pp. 135-62. See also Ann. 

 Mycol., V. (1906) p. 460. 



t Ann. Inst. Nat. Agron.,'v. fasc. 1 (1906) 45 pp., 22 figs. See also Bot. Cen- 

 tralbl., cii. (1906) pp. 585-6. 



X Comptes Rendus See. Biol. Paris, Ix. (1906) pp. 975-7. See also Bot. 

 Centralbl., cii. (1906) p. 583. 



§ Bull. Acad. Sci. Cracovie CI. Sci. Math. Nat., 1906, pp. 254-7 (1 pi.). See also 

 Ann. Mycol., v. (1906) p. 463. 



II Rabenhorst's Kryptogamen Flora, i. Abt. 8, lief 102 (Leipzig, 1906) pp. 661- 

 704 and pp. 705-52. 



