GENUS BACILLUS 



317 



identified B. icteroides Sanarelli as belonging to this group. 

 Gushing 10 placed a number of other bacteria such as the para- 

 colon and paratyphoid, the bacillus of psittacosis of Nocard 

 and the "microbe de la septicemie des veaux" of Thomassen 

 in .this group which Durham 11 designates "The Gaertner 

 group." This group stands intermediate between B. coli and 

 B. typhosus. 



While these bacteria are very closely related, there seem 

 to be quite distinct minor differences between certain of them. 

 Others are not easily differentiated. In many instances it 



Fig. 66. Bacillus suipestifer in a smear preparation. (After Smith). 



can not be positively done. Moore isolated a non-motile or- 

 ganism that could not be differentiated from B. suipestifer 

 except by the absence of flagella. Smith has described a 

 similar organism isolated by Prof. Burrill. 



Morphology. A rod shaped organism varying in size 

 according to the medium in which it has developed. From 



10 Gushing. Johns Hopkins Hospital Bulletin,, Vol. XI (1900) p. 



156. 



"Durham. The Lancet, Vol. I (1898) p. 154. 



