DISEASES OF THE SPLEEN, 



311 



involving the head of the pancreas in its mass, together with the 

 portal vein, the upper extremity of the ductus choledochus, and 

 the duodenum. In the liver a large number of small whitish 

 tumors were found, from the size of a millet seed to that of a 

 cherry, which formed part of the hepatic tissue. Microscopic ex- 

 amination of the principal neoplasms and of the tumors of the 

 liver showed lobulated epithelioma. 



Several similar observations have been related by other authors, 

 mainly by Friedberger. 



DISEASES OF THE SPLEEJST. 



Diseases of the spleen are not more frequent in our domestic 

 animals than in the human race. Most of the pathological works 

 do not even mention it. The obscure functions of this organ, and 

 its deep location, which removes it from the influence of external 

 agents, give a good and sufficient reason for the extreme rarity of 

 primary diseases of this organ. The alterations which are found 

 in it are almost always under the influence of a general morbid 

 condition, which is diathetic or infectious. We find, however, in 

 the veterinary journals a few observations relative to congestion, 

 inflammation, and rupture of the spleen. 



I. SPLENIC CONGESTIONS. 



They are either active or passive. Active congestions of the 

 spleen have been observed in all our animals, but particularly in 

 the ox, the sheep, and the dog. Their etiology is little known. 

 The main causes which have been assigned are : the sudden plethora 

 resulting from a very rich alimentation, when animals used to poor 

 feeding are suddenly given a large quantity of food, or placed in 

 abundant and watery pastures ; also, the feeding of pulp, the over- 

 loading of the rumen, excess of work, and damp heat. 



Passive congestions, which are caused by some obstruction to 

 the splenic vein, the portal vein, or the posterior vena cava, are so 

 much the more intense as the interference to the circulation is most 



