ZOOLOGY AND BOTANY, MICROSCOPY. ETC. 89 



UredineaB. — E. Fischer * has made a series of culture experiments 

 with Uromyces carijopJiilUnus, commencing with secidiospores taken 

 from Euphorbia (jorardiana and with them infecting Saponaria ocymoides 

 and Tunica prolifcra. He estabhshed that in the Uromyces there were 

 two forms represented, one which formed Uredospores on 2\micaproJifera, 

 and only very rarely infected the Saponaria plants, and a second which 

 grew freely on Saponaria ; whether the latter grows also on Tunica is 

 still undetermined. There is no morphok^gical difference between the 

 two fungus forms. 



F. 1). Kern f describes two submerged species of Uromyces on 

 Aristida sp. One of these has an ^cidium form on Plantayo sp. The 

 other has only one form, the Uredo, He also describes a new species 

 on Spartiua ylahra. 



Study of TJstilagineae.t — Felix Rawitscher has re-examined the 

 life-history of the smuts, and has confirmed the statements of Dangeard 

 and Lutman that on spore-formation there is a fusion of nuclei. In 

 UstiJago Carho there is, at germination, a formation of clamp-connexions 

 and copulation of sporidia with a passing over of the nuclei, so that a 

 binucleate mycelium is formed. The cells of the vegetative hyphse are 

 thus always binucleate, and provide the primordial spore-layer from 

 which arise the spores after fusion of two nuclei. In U. Maydis there 

 was neither formation of clamp-connexions nor copulation, and the 

 hyphal cells were all uninucleate ; but shortly before spore-formation, 

 a wall between two neighbouring cells breaks down and a binucleate 

 spore-cell is formed, from which is developed the uninucleate spore by 

 fusion of the nuclei. 



Morphology and Parasitism of Rhizoctonia.§ — F. J. F. Shaw 

 has investigated forms of this fungus which he found infecting various 

 plants, a severe outbreak of the disease having occurred at Pusa in 

 India during the rainy season of 1910. A Basidiomycetous fungus, 

 Corticium vagum, was associated with the Rhizoctonia. Shaw gives an 

 historical account of the fungus, and descriptions of the effects produced 

 by it on jute, cotton, cow-pea and ground-nut, with the results of his 

 experiments in cross-infection. In most cases the disease followed, 

 though a certain amount of physiological specialization was proved. 

 He discusses the connexion between Rhizoctoma and higher forms of 

 fungi. The perfect form, he concludes, is the Basidiomycete, which 

 has been identified as Corticium vagum. 



Mycological Notes. || — F. von Hohnel contributes a long paper 

 dealing with species already described, and many new to science collected 

 in Java. Among them there are many species of Nectria criticized and 

 re-described. The new genera established are 3IonfagneUina (Pyreno- 



* Mycol. Centralbl., i. (1912) pp. 307-13. 



t Torreva, ii. (1911) pp. 211-14. See also Centralbl. Bakt., xxxv. (1912) p. 357. 



X Zeitschr. Bot., iv. (1912) pp. 673-706 (1 pi. and 20 figs.). 



§ Mem. Dept. Agric. India, iv. (1912) pp. 115--53 (11 pis.). 



II SB. Akad. Wiss. Math.-Nat. KL, cxxi. (1912) pp. 339-424 (2 pis. and 7 figs.). 



