It is seen from the above table that the new race con- 

 stantly shows a higher maximum gas pressure than the pa- 

 rent type. This is true of all sugars used, though the per 

 cent, of excess is greater in the saccharose and maltose tests 

 than in the glucose. In about half the experiments the 

 maximum pressure was reached at the same time in each 

 type of B. coli, while in the others sometimes the one and some- 

 times the other type reached its maximum first. But there 

 seems to be no correlation between the relative times re- 

 quired to reach the maximum and the per cent, of excess gas 

 pressure in the new type. There is further no constant re- 

 lation between the temperature and the per cent, of excess 

 gas pressure of the new race. 



The gas formed in Smith fermentation tubes by race A 

 and the check was tested and the per cent, of CO2 found to 

 be approximately the same for each. 



Glucose broth cultures inoculated with race A and the 

 check were tested with Fehling's solution after fifty days' 

 growth — about seven days at incubator and about forty- 

 three days at room temperature. Both gave a positive glu- 

 cose reaction, and in about the same degree. 



On Endo agar both race and check produced the charac- 

 teristic reddening of the medium, and there was no marked 

 difference in the amount of color. 



To determine the relative sensibility of the new race and 



