CHARACTERISTICS OF THE COLON-AEROGENES GROUP 93 
starch and mannitol. 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 
Adonitol Adonitol 
(positive) (negative) 
Number Per cent Number Per cent 
IMAG! stencils ss snseaseetees + 61 44.20 9 7.20 
_ 17 55.79 116 92.80 
Saccharose ................ + 139 100.00 104 82.53 
_ 0 0.00 22 17.46 
Raffinose .................. + 139 100.00 105 83.33 
_ 0 0.00 21 16.66 
Stareh: sjsscshaeciisicenioivens + 78 59.09 26 21.13 
_ 54 40.89 97 78.86 
WOUND ei tcccecsieesey oes. + 7 7.52 9 8.41 
_ 86 92.47 98 91.58 
Mannitol “oct ti awee eieow sa + 132 97.05 p 41 32.80 
_ 4 2.94 84 67.21 
Glycerol: ose ey sek secede + 76 82.60 62 58.48 
_ 16 17.39 44 % 41.50 
SAliCIN assis sien veges + 131 99.24 117 93.60 
_ 1 75 8 6.40 
DuleltOl ee ccssersa sai cn desnemare + 42 30.43 22 17.59 
_- 96 69.56 103 82.40 
