354 



MICRO-ORGANISMS AND FERMENTATION. 



Saccharomyces turbidans or Saccharomyces ellipsoideus II. 



Hansen. (Figs. 76, 77.) 



Usually a bottom-fermentation yeast. 



Sedimentary forms grown in wort : Oval and round cells 

 predominate ; sausage-shaped cells are rare (Fig. 76). 



It was separated from beers which showed yeast-turbidity ; 

 is a species which causes yeast-turbidity, and is more dangerous 

 than Sacch. Pastorianus III. If this species is cultivated in 

 wort near the maximum temperature for growth, the vegeta- 

 tion consists of round and oval cells. The temperature limits 

 for budding in wort are 40 C. and 0-5 C. Saccharose, dextrose, 

 laevulose, and maltose are fermented, but not lactose. 



Fig. 76. Saccharomyces ellipsoideus II. Han- 

 sen. Cell - forms of young sedimentary 

 yeast (after Hausen). 



Fig. 77. Saccharomyces ellipsoideus II. 

 Hansen. Film- forms at 28" to 3" 

 (after Hansen). 



Ascospore-formation (Fig. 58, 6) : 

 At 35 C. no ascospores are developed. 



33-34 the first indications are seen after 31 hours. 



33 27 



31-5 ,, ,, 23 ,, 



29 22 



25 27 



18 42 



11 5|days. 



" 55 55 " 55 



4 no ascospores are developed. 

 Size of spores 2 to 5 ju. 





