348 



INFECTIVE DISEASES. 



lungs are simultaneously affected are not numerous, and sometimes 

 the ' lungs may be found to be perfectly healthy in cases with 



Pig. 137. — Ulceeation of the Intestine in a Typical Case of Swine-Pbver. 



long-standing lesion of the intestine. Old pigs may linger on for 

 weeks, and ultimately recover, and in the meantime act as centres 

 for the dissemination of the disease. 



