BACILLUS OF MALIGNANT EDEMA 



469 



Koch/ who studied this infection in connection with his work upon 

 anthrax in 1881, called attention to the fact that the bacillus described 

 by Pasteur did not produce a true septicemia, and suggested the term 

 "Bacillus of malignant edema," which is now in general use. 



Gaffky ^ found that, apart from its presence in putrid material, the 

 bacillus occurred in the upper layers of garden soil and in dust. It 

 has since- been found to be widely distributed in nature and in the 

 intestines of animals and of man. Its wide distribution is unques- 

 tionably due to the great resistance of its spores. 



Morphology and Staining. — ^The bacillus of malignant edema is a 



Fig. 101. — Bacillus of Malignant Edema, (After Frankel and Pfeiffer.) 



long slender rod, not unlike the anthrax bacillus, but decidedly more 

 slender. Its average measurements are 1 micron in thickness and 3 

 to 8 micra in length. It usually occurs as single rods, but frequently 

 appears in long threads showing irregular subdivisions. Often no sub- 

 divisions can be seen and the threads appear as long, homogeneous 

 filaments. These threads are less frequently seen in preparations from 

 solid media than in those from bouillon or edema fluid. The bacilli 

 are motile and possess numerous laterally placed flagella. Their motil- 

 ity is never very marked and is often entirely absent. The bacillus 



' Koch, Mitt. a. d. kais. Gesundheitsamt, i, 1881, p. 52 et seq. 

 2 Gaffky, Mitt. a. d. kais. Gesundheitsamt, 1881. 



