CHAPTER III. 



MORPHOLOGY OF THE CHOLERAIC COMMA-BACILLI. 



A. The Comma-bacilli of Cholera-stools and of the Intestinal 

 Contents. 



As has been described by Koch, the single comma-bacillus 

 is a minute rod more or less curved, being a portion of a 

 small or large circle. Owing to this shape Koch named it 

 the comma-bacillus, a name which I think unfortunate and 

 inappropriate. As Koch has shown, and as we shall see 

 more fully below, there can be no doubt about the single 

 comma-bacillus being in its full development an element of 

 a vibrio or spirillum, and for this reason it is not appropriate 

 to speak of the species as Bacillus ; and for the same reason 

 the name cholera-bacillus is not more acceptable ; it implies, 

 besides, that this form of bacterium is peculiar to cholera ; 

 now although, as will be shown below, this peculiar shape of 

 the organism was unquestionably in the mind of Koch (see 

 loc. cit. p. 25) when he described his observations in Egypt, 

 India, and France, it is now known that these so-shaped 

 organisms, i.e. comma-bacilli, occur under several conditions 

 other than cholera. 



The comma-bacillus, then, occurs in the intestinal dis- 

 charges and in the contents of the lower ileum, chiefly as 



