THE ANAEROBIC BACILLI 769 



bovis). Symptomatic anthrax is an infectious disease occurring 

 chiefly among sheep, cattle, and goats. It is spoken of as 

 "quarter-evil" or "blackleg." The disease has never been ob- 

 served in man. 'It was formerly confused with true anthrax, 

 because of a superficial similarity between the clinical symptoms of 

 the two maladies. Bacteriologically, the two microorganisms are in 

 entirely different classes. 



Symptomatic anthrax is of wide distribution and infection is 

 usually through the agency of the soil in which the bacillus is present, 

 in the form of spores which may retain viability .for several years. 





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FIG. 76. BACILLUS OP SYMPTOMATIC ANTHRAX. After Zettnow. 



Morphology and Staining. The bacillus of symptomatic anthrax 

 is a bacillus with rounded ends, being about four to six micra long, 

 and five-tenths to six-tenths inicra wide. It is usually seen singly 

 and never forms long chains. The bacillus in its vegetative form 

 is actively motile and possesses numerous flagella placed about its 

 periphery. In artificial media it forms spores which are oval, 

 broader than the rod itself, and placed near, though never actually 

 at, the end of the bacillary body. This gives the bacillus a racket- 

 shaped appearance. 



It is readily stained with the usual anilin dyes, but is easily 

 decolorized by Gram's method of staining. However, von Hibler 

 claims that when, very carefully stained the bacillus can be shown 



