BACILLUS AEROGENES CAPSULATUS 381 



in the form of flattened spheres, ovals, or irregular masses, beset with 

 hair-like projections. Bouillon is diffusely clouded, and a white sedi- 

 ment is formed. Milk is rapidly coagulated. 



Pathogenesis. Usually non-pathogenic in healthy animals, although 

 Dunham found that the bacillus taken freshly from human infection 

 is sometimes very virulent. When quantities up to 2.5 c.c. of fresh 

 bouillon cultures are injected into the circulation of rabbits and the 

 animals killed shortly after the injection, the bacilli develop rapidly, 

 with an abundant formation of gas in the bloodvessels and organs, 

 especially the liver. The following is one of the best methods of obtain- 

 ing the bacilli : The material suspected to contain the bacillus alone 

 or associated with other bacteria is injected into rabbits, which are 

 killed, kept at 37 C., and cultures made twenty-four hours later from 

 their bodies. 



It is suggested by Welch that in some of the cases in which death 

 has been attributed to the entrance of air into the veins the gas found 

 at the autopsy may not have been atmospheric air, but may have been 

 produced by this or some similar micro-organism entering the circula- 

 tion and developing shortly before and after death. The bacillus has 

 been found in the dust of hospitals. 



