438 SIMPLE TUMOURS. 



ulcerates by a slow, degenerate, and non-suppiirative process — 

 being seemingly converted into melanotic matter — and allows 

 more or less of the contents of the tumour to escape. As the 

 tumours grow the natural tissue of the part withers, its place 

 being taken up by the melanotic matter. 



The animal does not seem to suffer much inconvenience, ex- 

 cept from the effects of friction upon the surface of the tumour 

 when it comes in contact with contiguous parts. Thus a tumour 

 on the tail will become sore if it presses upon another tumour 

 on the vagina, or if by its weight it presses heavily upon the 

 opposing healthy skin, or when the tumour or tumours are so 

 heavy as to prevent the animal from elevating its tail during 

 progression. 



Without entering further into the details of the symptoms, it 

 may be concluded that a black tumour in any part of the body 

 may be called melanosis. 



Melanotic growths are neither very hard nor very soft, especi- 

 ally the external ones. Those found in the internal parts of the 

 body are much softer. The colour varies in shade from a dark 

 brown to the deepest black. 



Melanosis is generally confined to aged animals, but I have 

 seen it manifested in a five-year-old grey horse, and become 

 rapidly developed in various parts of the body. 



The treatment of melanosis is early removal, when it, as well 

 as other malignant growths, may be checked for a time ; but, as 

 already stated, its recurrent nature is so great as to preclude the 

 hope of permanent eradication. 



Lymphadenoma or Lymplio-mrcoma. — This is another form of a 

 malignant and fatal growth occurring in all the patients of the 

 veterinary surgeon, as well as in man, arising very often from no 

 appreciable cause, being sometimes of very slow, sometimes of 

 very rapid growth ; differing from other malignant tumours in 

 one particular only, namely, that it seldom invades but one kind 

 of tissue — that of the glandular system, but as certainly prov- 

 ing fatal as a tumour presenting all the characteristics of the 

 most potent malignancy. 



When of a very slow growth, and situated in some external 

 glands — (I have seen it in the lymphatic glands of the head and 

 neck remain passive as it were for years, ultimately develop in 

 the internal organs, and prove fatal)— it is termed a hjmplioma, 



