CHARACTERISTICS OF THE COLON-AEROGENES GROUP 



93 



starch and maniiitol. It is entirely possible that this differ- 

 ence is due to the fact that nearly all of the adonite + cul- 

 tures were freshly isolated from feces while the adonite - 

 cultures came for the most part from dried grains. To ac- 

 count for these differences in this way, it is necessary to assume 

 that the fermentative abilities of aerogenes become attenuated 

 by exposure to unfavorable conditions. While there is some 

 circumstantial evidence to support this view, it is by no means 

 established. On the evidence of the fermentative reactions 

 these varieties have only a little more substantial basis than 

 the communis and communior of the B. coli group, but, as 

 will be pointed out later, they may serve a useful purpose 

 in indicating the probable source of the organism. 



TABLE IV 



CORRELATION OF ADONITOL FERMENTATION WITH OTHER PHYSIO- 

 LOGICAL CHARACTERS 



