SACCHAROMYCES. 365- 



Saccharomyces mali Duclaux Kayser 



was discovered in cider, to which it imparts a good bouquet 

 and body. The cells are oval, and film-formation takes place. 

 At 15 C. spores are formed in 84 hours. It is a top-fermenta- 

 tion yeast, and ferments dextrose, but not saccharose, maltose, 

 and lactose. The sedimentary yeast lies very loosely in the- 

 flask. 



Saccharomyces unisporus n.sp. 



was discovered by J. C. Holm in Dutch cream. As regards 

 its behaviour to the sugars, it is most nearly allied to S. mali 

 Duclaux, for it ferments dextrose, but not saccharose, maltose, 

 and lactose. The cells are small and oval. Pastorianus forms 

 are also found in old cultures. The spores are round and 

 refractive. Only one fairly large spore is found in each celL 

 At 25 C. a few cells are found with ripe spores in 40 hours, 

 and at 15 C. in 72 hours. No true film-formation occurs,, 

 but, on the other hand, a yeast ring is formed in old cultures. 



Saccharomyces flava lactis Krueger. 



A. yeast cultivated from cheesy butter must be alluded to,, 

 which imparts a curious yellow colour, forms yellow colonies 

 on gelatine, and a yellow film on milk. The cells are 

 small, elliptical, and linked in chains. It ferments dextrose 

 with difficulty, and lactose not at all. On slices of carrot it 

 quickly forms spores. The most favourable temperature for 

 its growth lies between 18 and 20 C. It grows better on 

 slightly alkaline or neutral substrata than on acid. It quickly 

 liquefies gelatine. It only produces colouring matter when 

 it is in contact with air. 



Levure de sel a 



was discovered by Kr. Hoye in air analyses which were 

 carried out along the coast of Norway (Bergen and Christian- 

 sund). He used wheat paste mixed with about 17 per cent, 

 of sodium chloride as the substratum. The yeast is round, 

 and forms only a single spore in each cell. It thrives best in 



