ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 93 



less developed, while the ccenocentrum is larger. He compares, finally, 

 the development of the Albuginacefe with the Peronsporacese. 



Peronospora on Rheum undulatum.* — A. Osterwalder found that 

 the fungus causes small reddish spots on the leaves. The conidiophores 

 emerged from the leaf on the under side through the stomata. Oospores 

 were not seen, but the writer considers the species to be the same as 

 Peronospora pohjgoni. The conidiophores and conidia are of a slightly 

 violet colour. 



Biology of Cystopus candidus.f — Albert Eberhardt describes the 

 changes brought about in the host-plant by tbe presence of the parasite. 

 There was universal hypertrophy and distortion, alteration of form in 

 the floral organs, physiological changes in the cell-contents and in the 

 cell-forms, etc. He tested by culture experiments the specialisation of 

 the parasite, and found that within a limited range of host species the 

 conidia from Cystopus would infect easily. With conidia taken from 

 T ragopog on prate nsis it was impossible to infect any of the Cruciferae. 



Notes on Syncephalis.^: — Paul Yuillemin records a new species, 

 Syncephalis adunca, and makes an examination of the section Curvatce. 

 He insists on the autonomy of S. curvatce, which has been included under 

 S. cornu, and gives his reasons for doing so. The new species is yellow 

 in colour, and the spores occur in chains of four, the enclosing membrane 

 (merisporocyste) remains visible up to maturity. Vuillemin places it 

 between S. nigricans and S. curvata. 



Zygospore of Mucorini.§ — Paul Vuillemin has studied the process 

 of zygospore formation, especially in Sporodinia, with a view to watching 

 the fusion of the wall of the gametes. After the two copulatory branches . 

 have joined, the end of each remains for a time distinct, forming a 

 median wall, and a new layer is then laid down on each side of it and 

 on the external walls of the cells. Vuillemin notes that these two layers 

 fuse separately, the primitive central wall disappearing first. The later- 

 formed layers coalesce into one, to be in turn absorbed in the pro- 

 toplasm of the zygospore. 



New Genus of Phacidieae.j] — R. Maire and P. A. Saccardo found a 

 minute Discomycete parasitic on the leaves of Juniperus Oxycedrus, 

 half covered by the torn epidermis. The fungus had no excipulum, the 

 asci were tetrasporous, and the spores two-celled, brown ; characters which 

 are found in no existing genus. The writers have named it Didymascella 

 Oxycedri, one of the Phacidiere, and ^near to Didymascas in form and 

 structure. 



Fertilisation in Ascodesmis.lf — P. A. Dangeard finds at the origin 

 of the perithecium, branches of the hypliEe which fuse in pairs, as they 

 do in Gymnoascus. The number varies from six to ten for each fruit. 

 The two branches, which wind round each other in a spiral, are at first 



* Centralbl. Bakt , x. (1903) pp. 775-7 (3 figs.). f Tom. cit„ pp. G55-6. 



% Ann. Mycol., i. (1903) pp. 420-7 (1 pi.). 

 § Comptes Reudus, cxxxvii. pp. SCO— 71. 

 || Aim. Mycol., i. (1903) pp. 417-19 (4 figs.). 

 *j[ Comptes Rendus, cxxxvii. (1903) pp 528-9 



