192 



MICRO-ORGANISMS AND FERMENTATION. 



20-22 

 13-15 



6- 7 

 3- 5 



g- 51) 



Film-formation : 

 At 34 C. no film-formation occurs. 



26-28 feebly-developed film-specks are 



seen after - - 7-10 days. 



8-15 

 15-30 

 1 2 months. 



5- 6 



like Fig. 51, but without the large colonies. 

 2 3 no film-formation occurs. 

 Microscopic appearance of the cells in the films : 

 At 20-28 C. almost the same forms occur as in the sedi- 

 mentary yeast. 



At 13-15 C. strongly-developed mycelium-like colonies of very 



elongated, sausage-shaped cells (Fig. 51) are moderately frequent. 



In old cultures of films the cells are smaller than in the 



sediment ; very irregular and sometimes almost thread-like 



cells are found. 



SACCHAROMYCES PASTORIANUS II. (HANSEN). (Figs. 52, 53). 



Feeble top-fermentation yeast. 



Sedimentary forms grown in wort : Mainly elongated, 



FIG. 52. Saccharomyces Pastorianus II. (HANSEN)- Cell-forms of young sedimentary 

 yeast (after HANSEN). 



sausage-shaped cells, but also large and small, oval and round 

 cells (Fig. 52). 



