Microhic Diseases Individually Considered. 189 



Etiology and j^afhogeny. — Diseased animals dissem- 

 inate the virus in their fecal dejections and urine, 

 which are often mixed with blood and therefore 

 with hacteridia; frequently, also, the blood escapes to 

 the exterior directly by the nasal cavities. Their car- 

 casses, all parts of which contain the virus, are more 

 important sources of contagion ; hence, when these 

 carcasses are buried without any precautions being 

 taken to destroy the charbonous germs, they may 

 become the starting point of fresh cases. These 

 bodies become more directly dangerous when the 

 flesh is used for food. 



Contagion by direct contact is comparatively rare; 

 it occurs when a person inoculates himself with char- 

 bon at a cut or any other recent wound, in cutting up 

 a charbonous carcase ; it also occurs when the dis- 

 ease follows the consumption of diseased meat, and 

 finally, by transmission, now well established, from 

 the mother to the foetus. 



Contagion most frequently takes place by indirect 

 contact, the germs having been previously distributed 

 in the surrounding media. The floor of sheds, the 

 soil and vegetation of fields occupied by diseased ani- 

 mals, become soiled by their dejections; the germs 

 thus deposited may contaminate the litter and fodder 

 and thus gain entrance to the alimentary canal of 

 herbivora. It is not necessary in this case, as w^as at 

 first believed, that the animals ingest at the same time 



Dr. Trumbower. {Rep. Board of Live Stock Commissioners of Ilh., 

 1893.) 



A few cases in cattle, in which the diagnosis was confirmed by 

 competent bacteriologists are reported from Delaware. (Fifth An, 

 Rep. of the Del. College Agric. Experiment Sta., 1892, p. 45.) — D.] 



