SAC FUNGI IN PARTICULAR 



141 



menting milk. Kefir grains, which include the above yeasts, a Torula, 

 and 3 bacteria {Bacillus caucasicus, etc.) are added to the milk as a 

 starter. The fermentation of the milk results in the formation of alcohol 

 lactic acid and carbonic acid. Mazum (Matzoon) an Armenian drink, 

 is prepared by adding a white, fatty cheese-like mass, to milk. The 

 starter includes colored yeasts Oidium laclis, mould fungi, a yellow 

 Sarcina, Bacillus subtilis, some cocci. Bacterium acidilactici a.nd Saccharo- 

 niyces anomalus. The only species of yeast, which can be recognized 

 immediately by microscopic examination, is Saccharomyces Ludwigii, 

 with its lemon-shaped vegetative cells, on the point of which a wart 

 makes its appearance, which is cut off by a septum from the rest of the 

 cell. This species is transitional to those included in the genus Schizo- 

 saccharomyces. The form of Saccharomyces Ludwigii suggests S. 

 apiculatus, which is unequally dumbbell-shaped. The genus Tonda 

 according to Hansen includes yeasts similar to Saccharomyces, but 

 which do not form endospores, a typical mould growth, and which 

 produce alcohol in all percentages. They are widely distributed in 

 nature. 



Schroter in Engler's "Die naturlichen Pflanzenfamihen" recognizes 

 only two genera in the yeast family, namely, Saccharomyces and Mono- 

 spora. The reproductive cells of the former have two to eight (seldom 

 one to three) spores and the spores are spheric, or ellipsoidal, while the 

 needle-shaped spores of Monospora are borne singly in reproductive 

 cells, or asci. Hansen^ considers Monospora to be a doubtful form of 

 yeast {Saccharomyces douteux), as also the genus Nematospora. He 

 recognizes the following genera: Saccharomyces, whose spores have a 

 single membrane and the cells reproduce hyhxiddrng; Zygosaccharomyces, 

 where the asci are associated with conjugation; Saccharomycodes, whose 

 spores have one membrane and sprout into a promycelium; Saccharo- 

 mycopsis, whose spores have two membranes; Pichia with hemispheric 

 or angular spores and Villia with citron-shaped spores. Lafar in his 

 book on "Technical Mycology" (II, part 2, page 274) gives an analytic 

 summary of the genera which he believes should be recognized. The 

 position of such genera as Zygosaccharomyces, Saccharomycopsis, 

 Schizosaccharomyces with respect to nearly related fungi is presented 

 and discussed with a diagrammatic scheme of relationship by 



^ Hansen, E. Chr.: Grundlinien zur Systematik der Saccharomyceten. Centr. 

 f. Bak., 1904. 



