300 SUMMAEY OF CURBENT RESEARCHES RELATING TO 



MMzodonia violacea was found in vigorous development on Tri- 

 folium repens, pratense, and Jiybridum, usually attacking the upper 

 part of the root, causing it to put out a number of new roots. Eipe 

 sporangia were found only on completely rotten roots. 



New Peronospora of the Vine.* — Sig. G. Arcangeli has observed 

 on a number of vine-stocks from seeds brought from Cochin-China a 

 Peronospora differing from P. viticola dBy. in the smaller size of the 

 spores; their length being 11-13 ix and their breadth 9-11 fx, instead 

 of a length of 16-23 ^ and breadth 12-15 /x, as in the latter species. 

 Since, however, the vines on which it was found were always in close 

 proximity to American vines attacked by the common Peronospora, 

 he is disposed to regard it as a degraded variety of the latter, and 

 proposes the name Peronospora viticola dBy. var. Ampelocissi. 



Oidium albicans.f — Herr H. Plaut contests Grawitz's view that this 

 fungus (" der Soorpilz ") is identical with Mycoderma vini. He gives 

 the results in detail of cultivations of the microbe from men, children, 

 and fowls. In fermentable fluids it produces, when luxuriant, mode- 

 rately strong fermentation, while SaccJiaromyces Mycoderma produces 

 only very slight fermentation, and soon dies. The Oidium shows no 

 intercellular formation of spores, while, according to Eeess and 

 Cienkowski, S. Mycoderma does. In its yeast-form the Oidium is 

 more nearly spherical, S. Mycoderma ellipsoidal or fusiform. Pure 

 culture of Oidium reproduces the same form ; that of >S^. Mycoderma 

 remains without result. The author considers the Oidium as more 

 nearly allied to Monilia Candida Bon. or to Hansen's new species of 

 that genus. 



Mycology of Rome.:!: — Sigg. P. Baccarini and C. Avetta describe 

 116 Micromycetes from the neighbourhood of Eome, 98 of which are 

 new to the district. The following three species are described for the 

 first time, viz. : — Chsetomidium Pircunise, on rotting wood of Pircunia 

 dioica ; Metasphseria Ferulae, on dead branches of Ferula communis; 

 and Cucurhitaria hirtella, on rotten branches of Samhucus. 



Fossil Chytridiacea.§— MM. B. Eenault and 0. E. Bertrand find, 

 in the superficial cells of the seeds of Sphserospermum ohlongum, a 

 fossil gymnosperm from the upper " terrain houiller," the mycelium 

 and sporangia of a fungus which they name Grilletia Sphserospermi, 

 and refer to the ChytridiaccEe. The sporangia are naked, ovate, and 

 swollen on one side where the opening occurs, without any oper- 

 culum. It differs from other Chytridiaceae in the absence of an 

 operculum and neck to the sporangia, in the pi'esence of a mycelium, 

 and in its habit. It apx^ears to develope in the seeds when they 

 begin to decay. 



* Atti Soc. ToBcana Sci. Nat., iv. (1885) pp. 181-3, 



t Plaut, H., 'Beitr. zur systemat. Stellung des Soorpilzes,' 16 pp., 8vo, 

 Leipzig, 1885. Cf. this Journal, iii. (1883) p. 540. 



J Ann. Istit. Bot. di Eoma, i. (1885) Fasc. 2 (1 pi.). See Bot. Centralbl., 

 xxiv. (1885) p. 33. 



§ Comptes Eendus, c. (1885) p. 1306. 



