ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 237 



then dispose of the genera Dofhiopsls (4 species), Dothiorella (3'» species). 

 Rabenhorstia (6 species), Fuckelia (1 species), Placosph&ria (-3 species), 

 Ftisicoccum (36 species), Cylosporella (14 species), Cytospora (146 species), 

 and Centhospora (14 species). The second section of the Sphserioideae, 

 the Hyalodidymaj, is then commenced, characterised as follows : — Spores 

 elliptical, ovate, or elongated, bicellular, hyaline or greenish-yellow. 

 It comprises nine genera, — Ascochyta, Robillarda, Diylodina, Darluca, 

 Tiarospora, Actinonema, Cystotricha, Rhynchophoma, and Cytodiplospora. 

 Of tbese the following are dealt with :—Ascochyta (157 species), Robil- 

 larda (3 species), Dlplodina (100 species), aud 4 species of Darluca. 



Lamination and Staining- of Yeast-cell Membrane. * — Dr. C. 

 Becker records experiments with yeasts which yielded results quite 

 different from those obtained by Casagrandi. f Casagrandi maintained 

 that the yeast-cell membrane was not a single homogeneous sheath, but 

 was composed of two or more layers, visible in young as well as in old 

 cells. He found that the membrane was stainable by means of anilin 

 dyes, the most suitable being methylen-blue and Hanstein's anilin. At 

 the instigation of Herr H. Will, the author cultivated yeasts with thick 

 membranes, but after fourteen days' growth no lamination was detected, 

 though by means of chemical reagents (1 per cent, chromic acid and 

 1 per cent, osmic acid) this appearance was produced in some cells. 

 In ordinary brewer's yeast and in young cells the lamination was not 

 observed even when successively treated with alc.diol, ether, and chloro- 

 form, alcohol and chlor-zinc iodide, 3 per cent, hydrochloric acid, and 

 stained with iodine-green and fuchsin. Hence lamination of the yeast- 

 cell membrane is not an ordinary phenomenon, though it may occur 

 when the membrane is unusually thick, as in resting-cells and in yeasts 

 which have fermented very strong worts. The author- was no more 

 successful in his attempts at direct staining of the membrane, though 

 Casagrandi' s method was carefully followed After about three weeks' 

 treatment with Hanstein's anilin, a more or less clear staining of the 

 membrane was obtained. The stain was, however, easily removed by 

 means of water, and still more easily by alcohol. Methylen-blue failed 

 to impart any stain to the membrane, even after a treatment lasting 

 several months. Thus the cell-membrane was stained only by means of 

 prolonged treatment with Hanstein's anilin and the previous action of 

 hydrochloric acid (about 4 per cent.). 



Utilisation of Pare Yeasts in Wine Fermentation.^ — In a com- 

 munication on the utilisation of pure yeasts in the fermentation of 

 wines, Prof. E. Chodat explains the advantages of adopting this method, 

 and details the results obtained from a red wine of Crete. 



Six species of Saccharomyces were isolated from this wine. One (v.) 

 belonged to the S. apiculatus group ; the rest were true yeasts. Yeast i. 

 produced in sterile must containing 19*35 per cent, glucose, 5*78 per 

 cent, alcohol (vol.), 0-833 per cent, tartaric acid; ii. must, 19*35 per- 

 cent, glucose, 8 * 18 per cent, alcohol (vol.), * 66 per cent, acid ; iii. must, 

 17*86 per cent, glucose, 5*39 per cent, alcohol, 1*04 per cent, acid; 



* Zeitschr. f. d. ges. Brauwcsen, xxii. (1899) p. 597. See Centralbl Bakt. u. Par., 

 2" Abt., vi. (1900) pp. 24-6. t Cf. this Journal, 1897, p. 422, and 1898, p. 224. 

 X Arch. Sci. Phys. et Nat, viii. (1899) pp. 588-9. 



