YEASTS AND MOULDS. 579 



Saccharomyces sphsericus. Cells varying in form ; the 

 basal ones of a colony oblong or cylindrical, 10 to 15 /x long, 

 5 /x thick ; the others, round, 5 to 6 /A in diam. United in ramified 

 families. Spores unknown. 



Saccharomyces anomalus (Hansen). Cells small, oval, and 

 sometimes elongated. Spores are hemispherical, with projecting rims 

 at the base. They were found in impure brewery yeast. 



Saccharomyces mycoderma (Mycoderma, cerevisice et vini). 

 Cells oval, elliptical, or cylindrical, 6 to 7 /x long, 2 to 3 /x thick, 

 united in richly-branching chains. Spore-forming cells may be 

 20 /x long. Spores 1 to 4 in each mother-cell. The colonies in 

 gelatine are greyish and filmy. They form the so-called " mould " 

 on fermented liquids, arid develop on the surface without exciting 

 fermentation. When forced to grow submerged, a little alcohol is 

 produced, but the fungus soon dies. They occur on wine, beer, fruit- 

 juices and sauerkraut. 



Saccharomyces albicans (Oidium albicans, Fungus of thrush). 

 Cells round, oval, or cylindrical, 3*5 to 5 /x thick ; the cylindrical 

 cells 10 to 20 times as long as they are thick. The bud- colonies 

 mostly consist of rows of cylindrical cells, from the ends of which 

 oval or round cells shoot out. Spores form singly in roundish cells. 

 In plate-cultivations the colonies are pure white. In the depth 

 of gelatine a filament is formed composed of white colonies, some 

 with ray-like processes extending into the gelatine. On potato the 

 fungus forms a rapid white growth, and on bread also. They 

 can be easily cultivated in a nutrient solution containing sugar 

 and ammonic tartrate. The cells germinate according to the rich- 

 ness of the fluid in sugar ; they either grow into long threads, 

 or, in a very strongly saccharine solution, many daughter- cells are 

 formed and bud out in various directions. According to Klemperer 

 the thrush-fungus is pathogenic in rabbits, death taking place 

 twenty-four to forty-eight hours after an intravenous injection of 

 a pure- culture. Long mycelial threads are found in the internal 

 organs. They occur on the mucous membrane of the mouth, 

 especially of infants, in greyish -white patches, which consist of 

 epithelium, bacteria, yeasts, and the mycelia of various moulds. 



Saccharomyces pyriformis (Marshall Ward). Cells oval. 

 They convert saccharine solutions containing ginger into ginger- 

 beer. They occur with other micro-organisms in the so-called 

 " ginger-beer plant." 



Saccharomyces glutinis. Cells round, oval, or short 

 cylinders, 5 to 11 /x long, 4 /x wide, isolated, or united in twos. 



