STEEPTOCOCCUS HEMOLYTICUS 



191 



incubation. To attain this result the cultures of necessity 

 must have produced acid at varying rates. That this was true 

 is brought out by the curves which show a tendency toward 

 convergence after the second hour. From the data in table 8 it 



Fig. 7. 



Hours 



Experiment X. The Influence of Initial Ph of Broth Upon the 

 Rate op Acidity Formation 



appears that culture (4) exhibited the shortest lag (two hours) 

 though culture (5) showed the most rapid rate of acid formation 

 during the maximum period, namely, a lowering of 0.625 Ph 

 against a lowering of 0.425 Ph in the cases of (4) and (3). Culture 



