Parasites of the Liver. 333 



embryos of parasites taken in with the food, and which afterward 

 make their way into the bloodvessels, tend to make the hepatic 

 capillaries their first resting point, and to penetrate into the liver 

 parenchyma. Another common channel of approach is through 

 the common bileduct. 



The diseases resulting from the presence of parasites in the 

 liver are all more or less directly communicated from animal to 

 animal and would thus come especially under the head of sanitary 

 medicine and police, but as the majority do not rise to the im- 

 portance of a plague, these will be treated of here, as, in the 

 main, demanding private rather than government control. 



MONOCERCOMONAS HEPATICA. 



This is an infusorial organism discovered by Rivolta in the 

 liver of a young pigeon. It varied from 6 ;«. to 8.5 /a in diameter, 

 and through its amoeboid movements varied its shape from round, 

 to oval or angular, and moved by the aid of one or two fiagelli. 

 Its protoplasm was granular, with two nuclei and vacuoles. The 

 affected liver was firmer than in the normal condition, and con- 

 tained numerous colonies of the parasite, with necrosed areas 

 varying in size from a pin point to a pea, or hazelnut. These 

 were especially numerous and confluent toward the borders of the 

 liver, and resembled caseated tubercles (caseous hepatitis). The 

 adjacent acini were congested and covered with a gelatinoid 

 exudate. 



An attempt was made to transmit the disease by feeding a 

 young pigeon on hepatic pulp containing the living infusoria. 

 "When killed .six days later numerous cellular bodies, of variable 

 form, and each having a granular nucleus near its periphery, 

 were found in the small intestine, which might be the young 

 monocercomanus, but none could be shown to have as yet invaded 

 the liver. 



SACCHAROMYCES GUTTULATUS. 



This cryptogam, which has been found in the intestinal canal 

 of rabbit, ox, sheen and pig, has been discovered by Remak in 

 the bile-ducts of the rabbit, where it accumulates in masses of a 

 firm or caseous consistency which might be mistaken for tubercles. 



PSOROSPERMOSIS. COCCIDIOSIS. 



This is especially common in the liver of the rabbit, but has 



