422 



K. G. DERNBY AND J. BLANC 



many aspects this is undesirable. Already earlier authors have 

 pointed out that these anaerobes do not change the acidity or 

 alkalinity of the medium. 



TABLE 2 



Grotvth of Clostridium sporogenes 0. 



Time of incubation, sixteen hours. Temperature 37° 



TABLE 3 



Growth of Clostridium histolyticum 



Time of incubation, sixteen hours. Temperature, 37° 



In tables 2, 3 and 4 some of our experiments are recorded. 



Our method, though apparently arbitrary, and giving no ab- 

 solute basis for the calculation of the rate of growth, yet provides 

 by the range of comparison which it affords, a quite adequate 

 standard for all practical purposes. 



In figure 1 the results from the tables 2, 3 and 4 are graphically 

 represented. Even if the point for the optimum pH and the 

 limits in the different cases change, we may as a whole state that 



