2o8 Theobald Smith 



I have omitted from the above record four additional cult- 

 ures of B. cholera stiis, three of which are identical with II 

 and III so far as the quantity of gas produced is concerned ; 

 the fourth corresponds to IV in this respect. In all varieties 

 of this sub-group the behavior in glucose bouillon is precisely 

 the same. There is a rapid evolution of gas on the first and 

 the second day ceasing promptly on the fourth or fifth. The 

 growth subsides at the same time. The culture fluid becomes 

 strongly acid. 



The action of this entire group on saccharose and lactose in 

 bouillon is negative and hence I omit any tabulation of the 

 records. Unless the bouillon is free from muscle glucose there 

 may have accumulated, after one or two weeks, a certain 

 amount of gas corresponding to that developed in the same 

 bouillon free from any additions. This may amount to 15 or 

 20 per cent, of the contents of the closed branch. A glucose- 

 free bouillon recently tried remained free from anj- gas. That 

 there is, in such tubes, no action on the sugar is proven bj^ 

 the feeble transitory acid reaction when gas is formed to a 

 slight extent. This soon changes to an alkaline reaction in 

 the bulb. When glucose is entirely absent the acid reaction 

 fails to appear. 



B. lactis aerogenes Escherich^ The cultures which I 

 have tested differ from those of B. coli in certain minor but 

 definite characters. Thej' were non-motile and provided with 

 more or less zooglcear or intercellular, but not viscid, sub- 

 stance often recognizable on the border of the hanging drop as 

 a distinct capsule. When these bacilli are cultivated on solid 

 media this capsular substance manifests itself by a regular 

 spacing between the individual bacilli when these are massed 

 together. The growth on potato is richer and of a paler yel- 

 low color than that of B. coli. The surface colonies on gelatin 

 are usually fleshier than those of the latter and frequently re- 

 semble little pearly drops. In old bouillon cultures there is 

 noticeable an even stronger fecal odor than that arising from 

 similar cultures of B. coli. I give the above characterization 

 mainly becaiise the species does not seem to be any more stable 

 in its minor characters than B. coli. The following table gives 

 the gas production of the only culture thoroughly examined. 



