GROWTH OF YEAST 



181 



is termed the logarithmic phase. This is followed by a period 

 of retardation due to the operation of factors such as the ac- 

 cumulation of carbon dioxide and the lack of oxygen. This 



^ 10 



3 



3 



20 

 30- 



3 40 

 50- 



60- 



70- 

 80 



120 



153 



180 



218- 



232 



240 



Fig. ii. 



is a normal sequence : but departures from the normal may 

 result on varying the conditions of growth ; thus if the 

 seeding be heavy, but not excessive, the logarithmic phase 

 may disappear and retardation set in immediately after the 



