PRINCIPLES OF VETERINARY SURGERY 



551 



etc,) are seldom large enough to provoke grave digestive 

 disorders, but they may impede the return circulation or 

 compress the aorta, and produce oedema and ascites. They 

 may predispose to attacks of cohc or rupture of the intes- 

 tines, by traction on the mesentery. 



Melanosis of the liver may disturb its function and cause 

 degeneration and rupture. This termination is especially 

 frequent in melano-sarcoma. The splenic form generally 

 passes unnoticed, and is found only at the autopsy. 



Fig. 68a. 

 Melanosis of the Extremity of the Tail (Tail Elevated). 



The respiratory form characterized by infiltration of the 

 lungs, the pleura and the periphery of the heart manifests 

 itself by dyspnoeic symptoms of more or less intensity. The 

 respirations are alternately calm and accelerated. Some- 

 times the subject is seized with general tremors and ex- 

 hibits asphytic symptoms. Then again they may cause a 

 fatal hsemoptosis. In some cases they cause circumscribed 

 sudation by compressing the sympathetics. Bouley reports 

 a case in the horse that sweated copiotisly over the left side 

 of the head, neck and shoulder. Sometimes the melanotic 



