XV] ANAEROBIC BACILLI 397 



bacillus of malignant oedema. As in the case of the bacillus 

 of malignant oedema so also with our bacillus, larger doses 

 of culture are required for infection of guinea-pigs than of 

 the subcutaneous exudation, this latter on subcutaneous in- 

 jection proving more virulent than the artificial culture. In 

 our case, subcutaneous injection of five minims of the sub- 

 cutaneous exudation suffices to produce fatal infection within 

 twenty to twenty-four hours in a guinea-pig of 200 grammes 

 weight. 



Spores alone, or cultures five to seven days old in which 

 spore-formation is nearly completed, do not act as virulently 

 as young cultures when injected subcutaneously into the 

 guinea-pig, larger doses of the former being required to pro- 

 duce the same result as smaller doses of the latter. Doses, 

 which taken from recent cultures produce fatal results in 

 twenty to twenty-four hours, when taken from old cultures full 

 of spores produce only a transitory local swelling and transi- 

 tory constitutional disturbance. Neither mice nor guinea-pigs 

 are susceptible to infection by feeding with spores. 



Injected into the peritoneal cavity of the guinea-pig the 

 bacilli of young cultures produce fatal results in six to eight 

 hours ; the peritoneal cavity containing after death copious 

 sanguineous exudation full of the bacilli. 



The size of the bacilli is, length i'6 to 48 



,, ,, thickness O'S 



, , free spores is, length i "6 



• ,, ,, thickness O'S to i 



In size, shape, feeble motility, in the rapid liquefaction of 



sugar gelatine, in the characteristic changes produced in 



milk, our bacillus resembles the anaerobic Bacillus butyricus 



described by Botkin,i but Botkin's bacillus differs from our 



■^ Botkin, '* Ueber einen Bacillus butyricus," Zeitschrift f. Hygieveu. 

 Infectionskrank., bd. xi. p. 421. 



