ZOOLOGY AND BOTANY, MICKOSCOPY, ETO. 1033 



Tubercles on the Roots of Alnus and the Elaeagnaceae.* — In order 

 to establish that the bacteroid found in the tubercles on the roots of 

 these plants is peculiar to them, Dr. J. Brunchorst has carefully 

 examined the corresponding structures on the roots of Crataegus 

 prunifolia, Cyperus flaveseens, Juncus bufonius, JEsculus Hippo- 

 castanum, Cycas, Ceratozamia, and other Cycadeae, without finding any 

 organisms bearing the remotest resemblance to those found in Alnus, 

 Elseagnus, Hippophae, and Shepherdia. The structures in the parasitic 

 fungus, hitherto regarded as spores, the author now regards as spor- 

 angia, the contents of which break up, late in the summer, into spores 

 of extreme minuteness. Herr Brunchorst proposes for the parasite 

 the name Franlcia subtilis, probably identical with Woronin's and 

 Frank's Schinzia, and Mailer's Plasmodiophora. He now regards it 

 as belonging to the Hyphomycetes, but with a mode of formation of 

 its spores peculiar to itself. 



Protophyta. 



Physiology and Morphology of Alcoholic Ferments.f — Herr 

 E. C. Hansen devotes the latest instalment of his treatise on this 

 subject to the methods of obtaining pure cultures of Saccharomyces 

 and other similar organisms. He states that the formation of pellicles 

 (Kahmhautbildung) is a general phenomenon with all micro-organisms, 

 both with bacteria and with true fungi. It takes place with all forms 

 of Saccharomyces when the cells stand for a sufficient time with their 

 fermenting nutrient fluid. Under these conditions S. cerevisise and 

 S. ellipsoideus are transformed into S. Pastorianus, and a development 

 sets in of filiform and bacterioid cells. One condition for this 

 development is an abundant access of atmospheric air. It commences 

 at from 13°-15° C. 



Abnormal Secretion of Nitrogenous Substances by Yeasts and 

 Moulds. J — According to MM. U. Gay on and E. Dubourg, when yeast 

 is suspended in water, only a small quantity of nitrogenous matter 

 passes into solution, and this is not coagulable by heat. If the water 

 is replaced by concentrated solutions of such salts as potassium 

 acetate, oxalate, or iodide, sodium phosphate or sulphate, calcium 

 chloride, magnesium sulphate, tartar emetic, &c, the liquid dissolves 

 a considerable quantity of albuminoids which are either partially 

 coagulable by heat and acids or not coagulable at all. The total 

 amount of albuminoids dissolved, and the ratio between the coagu- 

 lable and non-coagulable portions depend on the nature of the saline 

 solution. After the yeast has been treated with these solutions, it 

 can still yield to water a considerable quantity of albuminoids 

 partly coagulable and partly non-coagulable. Many other soluble 

 substances behave in the same way as the above salts. If yeast is 



* Unters. a. d. Bot. Inst. Tubingen, ii. (1886) pp. 151-77 (1 pi.). See But 

 Gentralbl., xxvii. (18S6) p. 109. Cf. this Journal, ante, p. 272. 



t Meddel. Carlsberg Labor., ii. pp. 152-210 (8 pis. and 4 rigs.), with French 

 resume'. See Bot. Gentralbl., xxvii. (1886) p. 163. 



X Comptes Eundus, cii. (1886) pp. 978-80. 



