528 Veterinary Medicine. 



masses, and the morbid growth may have involved the capsule 

 and caused adhesion to the back of the diaphragm (Bachstadt). 

 The cut surface of the neoplasm is smooth, elastic, yellowish and 

 circular or oval in outline. It may have a variable consistency — 

 friable or tough, according to the activity of growth and the 

 relative abundance of cells and stroma. The portal glands are 

 hypertrophied and thrombosis of the portal vein is not uncommon. 



Microscopic examination of the dark red scrapings shows nu- 

 merous blood globules, intermixed with the round or spindle 

 shaped cells and nuclei of the tumor. Sections of the tumor 

 .show these cells surrounded by a comparatively sparse fibrillated 

 .stroma. The round cells may vary from .005 to .05 m.m. They 

 contain one or more rather large nuclei and a number of refran- 

 gent nucleoli. The nuclei are often set free by the bursting of 

 the cells in the .scrapings. They become much more clearly de- 

 fined when treated with a weak solution of acetic acid. Small 

 grayish areas in the ma.ss of the tumor repre.sent the original 

 structure of the liver, the cells of which have become swollen and 

 fatty. 



A liquid effusion more or less deeply tinged with red is usually 

 found in the abdominal cavity. 



Symptoms are those of a wasting disease, with some icterus, 

 sometimes digestive disorder, and a marked enlargement of the 

 liver. The last feature can be easily diagno.sed by palpation and 

 percussion. If an examination through the rectum detects the 

 enlargement and irregular rounded swellings of the surface of the 

 liver or spleen, or the existence of rounded tumors in the mesen- 

 tery or sub-lumbar region, this will be corroborative. The 

 precise nature of the neoplasms can only be ascertained after 

 dtath. 



Melanoma. Melanosis of the liver is comparatively frequent, 

 especially in gray horses, and above all when they are aging and 

 passing from dark gray to white. In many cases a more certain 

 diagnosis can be made than in sarcoma for the reason that primary 

 melanotic neoplasms are especially likely to occjir on or near the 

 naturally dark portions of the skin, as beneath the tail, around 

 tlie anus or vulva, in the perineum, sheath, eyelids, axilla, etc. 

 The extent of the disease is likely to be striking, the liver, next 

 to the spleen, being the greatest internal centre for melanosis. 



