378 



After thirty-six hours. — Fermentation decidedly established, 

 a thin layer of froth on the surface. Ferment-cells much more 

 numerous, and, for the most part, larger ; some solitary, others 

 in groups of two or three. Filaments of Bacterium as on pre- 

 ceding observation. 



After forty-eight hours. — Fermentation very active, a co- 

 pious frothy head, strong vinous odour. 



Ferment-cells have much increased, and may be seen in 

 various stages of germination ; some are solitary, others form 

 groups of two, three, four, or, occasionally, five ; and some of 

 the groups have begun to exhibit a disposition to branch ; some 

 of the cells have considerably increased in size. Bacterium fila- 

 ments abundant. 



After sixty hours. — Fermentation very active ; a copious 

 dense yeast has been deposited at the bottom of the flask ; the 

 fluid continues to exhale a strong vinous odour. 



Under the microscope the ferment-cells are seen to have 

 still multiplied, and branched groups, of from three to six 

 cells, are frequent. There is an evident general increase in 

 the size of the cells. Bacterium filaments abundant. 



After seventy-two hours. — Fermentation still very active, 

 but the fluid presents no change of importance since last ob- 

 servation. 



After eighty-four hours. — Fermentation has greatly sub- 

 sided. Cells still numerous throughout the fluid, but much 

 more so at the bottom, where they have collected into a copious 

 yeast. The cells of this yeast are mostly solitary, and larger 

 than the majority of the floating cells ; a great number of the 

 latter continue united in simple linear or branched groups. 

 Bacterium filaments are very abundant all through the fluid. 



A few hours after this the fermentation appeared to have 

 entirely ceased. The ferment-cells had almost all subsided to 

 the bottom. The Bacterium filaments continued abundant, 

 suspended at all depths through the fluid. 



The ferment-cells, when mature, are nearly spherical, and 



