172 BACTERIA 



in the superficial layers of the soil. From its habitat it 

 readily gains entrance to animal tissues. It has spores, but 

 though they are of greater diameter than the bacillus itself 

 they are not absolutely terminal. Hence they merely swell 

 out the capsule of the bacillus, and produce a club-shaped 

 rod. They form gas while growing in the tissues and in 

 artificial culture. External physical conditons have little 

 effect upon this bacillus, and the dried and even buried 

 flesh retains infection for a very long period of time. 



B. OF Symptomatic Anthrax B. of Malignant CEdema 



The third disease-producing microbe found naturally in 

 soil is that which produces the disease known as Malignant 

 CEdema. Pasteur called \\)\s gangrenous septiccemia. Unlike 

 quarter evil, malignant oedema may occur in man in cases 

 where wounds have become septic. Animals become inocu- 

 lated with this bacillus from the surface of soil, straw-dust, 

 upper layers of garden-earth, or decomposing animal and 

 vegetable matter. 



The bacillus occurs in the blood and tissues as a long 

 thread, composed of slender segments of irregular length. 

 It is motile and anaerobic. The spores are larger than the 

 diameter of the bacillus, and the organism produces gas; so 

 much is this the case in artificial culture, that the medium 

 itself is frequently split up. 



