318 BACILLI PATHOGENIC IN ANIMALS. 



cultivations were made in broth, and carried through 

 several generations. If Pasteur inoculated fowls in the 

 subcutaneous cellular tissue over the muscles of the 

 breast with these attenuated bacilli, only an inflam- 

 matory swelling of the cellular tissue, especially of the 

 muscle, occurred ; the affected portions of the muscle 

 soon became separated from the healthy by an abscess 

 wall, so that a sequestrum of the muscular tissue was 

 formed. This was absorbed with greater or less 

 rapidity, and usually had completely disappeared some 

 weeks after inoculation. The fowls which had thus re- 

 covered were then found to be immune against inocula- 

 tion with the most virulent bacilli. 



Discrepant re- The results of Pasteur's experiments could not be 

 obseryers tlier confirmed by Kitt and others. Cultivations on potatoes 

 and gelatine five or six months old, and always exposed 

 to air, showed the same virulence as fresh cultivations. 

 It is possible therefore that Pasteur's cultivations, which 

 were always made in fluids, were gradually overgrown 

 by other bacteria, and that thus the diminution in 

 activity was produced. 



Bacillus septicus agrigcnus. 



Septic earth These bacilli were first obtained by Nicolaier in the 

 author's laboratory, and at a later period on several 

 occasions from the earth of manured fields. These 

 bacilli agree, as regards their size, for the most part 

 with the two forms before mentioned, but they are usually 



Microscopical somewhat longer ; the same peculiar distribution of the 



5rs ' colouring matter is also at times seen, although not so 



frequently, nor so well marked. Kapid division occurs 



in cultivations, and hence, as a rule, there is only a trivial 



Cultivations, excess of the longitudinal diameter. On gelatine plates 

 the colonies present the appearance under a low power 

 of circular discs, with sharp outlines and of a finely 

 granular character ; the centre is yellowish-brown, and 

 the margin greyish-yellow, these two parts being sepa- 

 rated from each other by a dark ring. These differences 

 in colour gradually disappear at a later period, so that 



