396 MICRO-ORGANISMS AND FERMENTATION. 



a slight slimy sediment, which is only visible on shaking. 

 The ring increases in thickness, and grows towards the middle 

 of the flask, so that this is gradually filled from top to bottom 

 with a rose-coloured slimy mass. A true sediment is not 

 formed. The clots of slime which fall from the ring form a 

 more or less thick layer on the bottom. On taking out the 

 sample the liquid is quite ropy. No fermentation takes place 

 with dextrose, maltose, lactose, saccharose, raffinose, and 

 dextrin. Saccharose and raffinose are inverted. By the 

 cultivation of this species in wort with varying quantities of 

 alcohol, a small yeast ring is observed in eight days at 25 

 C. in wort containing 1 per cent, of alcohol. The ring is not 

 formed in presence of 2 per cent., and no development whatever 

 takes place in presence of 5 per cent, of alcohol. 



^ To determine how far the slime 



<, $ f> o _^ formation is influenced by the pro- 

 & j? <s& portion of sugar and albumen, the 



a ^ r? following experiment was carried out. 

 0s> ^Jo ^ n a P ure dextrose solution the de- 

 <se ^, <SP as** velopment was poor (1-5-10-20 per 

 ^ ^ao^ <^ & e cent, dextrose), and no yeast ring 

 ^ eSs> <*& formed, only a minute sediment. By 



^ ^ the addition of peptone the ring 



Fig. w.-Toruia b. Young culture formation is restored. When the 



(Brask). x 560. , _ 



quantity of sugar remains constant 



(10 per cent, dextrose), while that of peptone rises from 0-1 

 to 0-2, 0-5, and 1 per cent., the ring formation is favourably 

 influenced. With a constant quantity of peptone (0-5 per 

 cent.) and increasing quantities of dextrose (5-10-20 per 

 cent.) the slimy ring formation is reduced with increasing 

 quantity of sugar. This shows that the slime formation de- 

 pends upon the presence of albuminoids, and not upon that 

 of sugar. The surface colonies on wort - gelatine (10 per 

 cent.) are round, moist, and glistening, pale pink in colour, 

 and slightly arched. The young colonies have smooth edges, 

 the older show a depression in the middle and slight transverse 

 furrows at the edge. 



Torula c = Torula cinnabarina n.sp. The cells are pre- 

 dominantly of an elongated and oval shape, often provided 





