200 Manual of Veterinary Microbiology. 



tion of a second intra- venous injection, and also against 

 the subcutaneous inoculation of an otherwise mortal 

 virus; the reaction of the latter then consists only in 

 the formation of a curable abscess, the pus of which 

 contains the virulent germs. 



If the dose w^aich can be tolerated in the vessels is 

 exceeded, the typical disease ensues with the develop- 

 ment of tumors. Similarly, if, after the intra- vascular 

 injection of a vaccinating dose, a hemorrhage is pro- 

 duced in the connective tissue, a specific, fatal tumor 

 appears in the place of the solution of vascular con- 

 tinuity, the bacilli having penetrated into their media 

 of predilection. 



The disease is transmissible by way of the respira- 

 tory passages, the result being the same as by the blood- 

 vessels. Finally, the disease can be transmitted by 

 way of the intact digestive canal if the virus is very 

 active ; the tumors then appear in places remote from 

 the point of entry. 



Etiology and j^c^thogeny. — Symptomatic charbon is 

 endemic in certain countries; it prevails especially 

 during summer, its ravages being however less im- 

 portant than those of bacteridian charbon. Animals 

 inoculate themselves accidentally, and as small doses 

 confer immunity and this is transmitted from the 

 mother to the foetus, it results that part of the animals 

 exposed to the contagion escape its fatal efiects. But 

 those which at first receive a suflacient dose quickly 

 succumb. 



The virus seems to be capable of entering by diflfer- 

 ent ways. Wounds of the external integument in 

 favorable regions are more especially suited to its evo- 

 lution ; but the inhalation of dust charged with dried 



