182 MASS. EXPERIMENT STATION BULLETIN 167. 





VO 



^S 



6o 



55- 



SO 



¥5- 



■¥^ 



GzrcKVh I.- {T>>-cTeolysis) 



^a 



vz 



/ZO Uci^rs 



6 /Z /6 Z9 

 ■ Co^yTrol ., 



S/^T-ef/. eT-ysipclaf/s /j^ ^r)ec/'''o>^ (0-i=7. 6S) 



StrepT'. /acT'/Ci^s, •• - f^ = 7. 6Z) 



Graph 1 represents the proteolysis of Streptococcus erysipelatis and 

 Streptococcus lacticus in the media of which the hydrogen ion concentra- 

 tion is (H)= 2.24X10"^ and (H) = 2.40X10■^ respectively. The results 

 in these two media (the same within the limit of error) were especially 

 considered instead of the optimum hydrogen ion concentration for pro- 

 teolysis in the case of each organism. The reason for this is to be found 

 in an effort to comply with the purpose of this investigation. 



