CHAPTER II. 

 MALIGNANT EDEMA. 



BACILLUS (EDEMATIS MALIGNI (KOCH). 



General Characteristics. A motile, flagellated, sporogenous, an- 

 aerobic, liquefying, aerogenic, non-chromogenic, pathogenic bacillus of 

 the soil, readily stained by the ordinary methods, but not by Gram's 

 method. 



This organism was originally found by Pasteur* in putres- 

 cent animal infusions and called -by him (1875) Vibrion 

 septique. It was later more carefully studied and described 

 by Koch.f 



Distribution. The organism is widely distributed in 

 nature, being commonly present in garden earth. It is also 

 found in dust, in waste water from houses, and sometimes in 

 the intestinal canals of animals. 



Morphology. The bacillus of malignant edema is a large 

 rod-shaped organism with rounded ends, measuring 2 to 10 /w 

 by 0.8 to i.o [i. It is usually motile, and possesses many 

 flagella. It produces oval endospores centrally situated and 

 giving a barrel shape to the parent bacillus. 



Staining. The bacillus stains well with ordinary cold 

 aqueous solutions of the anilin dyes, but not by Gram's 

 method. 



Cultivation. The organism is a strict anaerobe, but under 

 conditions by which provision is made for the removal of 

 oxygen, grows well both at the room temperature and at that 

 of the incubator. It is not difficult to secure in pure culture, 

 being most easily obtained from the edematous tissues of 

 guinea-pigs and rabbits inoculated with garden earth. 



The colonies which develop upon the surface of gelatin 

 kept under anaerobic conditions appear to the naked eye 

 as small shining bodies with liquid, grayish-white contents. 

 Under the microscope they appear filled with a tangled 

 mass of long filaments which under a high power exhibit 



* "Bull. Acad. Med.," 1877 and 1881. 



t "Mittheilungen aus dem kaiserl. Gesundheitsamte," i, 53. 

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