BACILLUS OF MALIGNANT (EDEMA. 543 



catheterization. From the animal experiments of the 

 authors above mentioned, simple injection of pure cul- 

 tures of proteus into the bladder, without artificial sup- 

 pression of urine, invariably produces severe cystitis. 

 The fact that this organism grows in urine is sufficient 

 to account for the extension of the purulent process 

 finally to the kidneys. 



The proteus vulgaris is, however, a harmles parasite 

 when located in the mucous membrane of the nasal 

 cavities. Here it only decomposes the secretions, with 

 the production of a putrefactive odor. On the whole, 

 considering the very wide distribution of this organism 

 in nature, it is remarkable how few diseases are pro- 

 duced by it. 



BACILLUS OF MALIGNANT (EDEMA. 



This bacillus is widely distributed, being found in 

 the superficial layers of the soil, in putrefying sub- 

 stances, in the blood of animals which have been suffo- 

 cated (by invasion from the intestine), in foul water, 

 etc. It was discovered (1877) by Pasteur in animals 

 after injections of putrefying liquids, and named by 

 him " vibrion septique." He recognized its anaerobic 

 nature, but did not obtain it in pure culture. Koch 

 (1881) carefully studied this micro-organism, described 

 it in detail, and gave it the name " bacillus cedematous 

 maligni." It was isolated first in pure culture by 

 Liborius. 



Morphology. The oedema bacillus is a rod of from 

 0.8/2 to \IJL in width, and of very varying length, from 

 2// to 10// or more, according to .the conditions of its 

 cultivation and growth. It is usually found in pairs, 

 joined end to end, but may occur in chains or long 

 filaments. It forms spores, and these are situated 



