452 BACTERIOLOGY. 



Cattle, sheep, goats, guinea-pigs, and mice are sus- 

 ceptible to infection with this organism, and present the 

 conditions above described; whereas horses, asses, and 

 white rats present only local swelling at the site of inoc- 

 ulation. Swine, dogs, cats, rabbits, ducks, chickens, and 

 pigeons are, as a rule, naturally immune from the disease. 



Though closely simulating the bacillus of malignant 

 oedema in many of its peculiarities, this organism can, 

 nevertheless, be readily distinguished from it. It is 

 smaller; it does not develop into long threads in the 

 tissues; it is more actively motile, and forms spores 

 more readily in the tissues of the animal than does the 

 bacillus of malignant oedema. In their relation to ani- 

 mals they also differ, viz., cattle, while conspicuously 

 susceptible to symptomatic anthrax, are practically im- 

 mune from malignant oedema; and while swine, dogs, 

 rabbits, chickens, and pigeons are readily infected with 

 malignant oedema, they are not, as a rule, susceptible to 

 symptomatic anthrax. Horses are affected only locally, 

 and not seriously, by the bacillus of symptomatic an- 

 thrax; but they are conspicuously susceptible to both 

 artificial inoculation and natural infection by the bacil- 

 lus of malignant oedema. 



The distribution of the two organisms over the earth's 

 surface is also quite different. The oedema bacillus is 

 present in almost all soils, while the bacillus of symp- 

 tomatic anthrax appears to be confined to certain local- 

 ities, especially places over which infected herds have 

 been pastured. 



A single attack of symptomatic anthrax, if not fatal, 

 affords subsequent protection, while infection with the 

 malignant oedema bacillus appears to predispose to re- 

 currence of the disease. (Baumgarten.) 



