CAPPED ELBOW. 55 



even man himself. Melanotic cancer is most commonly 

 seen in gray horses, or tliose that turn white with age. A 

 small hard tumor is usually seen under the root of the 

 tail, and about the anus. 



When tumors of this kind are seen on gray horses, it 

 may reasonably be expected that growths of the same char- 

 acter will be found inside, on the spleen, stomach, and liver. 

 Horses so affected may work well for years, and may not foir 

 a month. The tumors increase in size ; when cut into, they 

 discharge a fluid as black as the ink of the cuttle-fish. 



Causes. As this disease is not seen in young gray horsea 

 until after they have almost turned white, it may be in- 

 ferred that the cause results from the loss, or want of the 

 usual pigment, or coloring matter, which gives color to the 

 hair, thus depriving the animal of some protection from 

 the air or sun. I think, however, that the true cause will 

 be found to be, not in the hss of the coloring matter, but 

 of its transfer from the skin and hair to the blood. Hence 

 the inky color of the contents of the tumors. This opinion, 

 which is my own, is still further corroborated by the fiict 

 that if the pus be taken from an abscess and injected into 

 the blood of a healthy animal, carbuncles containing pua 

 will soon manifest themselves. 



Treatment. Incurable; but when one of these tumora 

 breaks, treat it as an ordinary abscess, (which see.) 



Canine Rabies. — (See Hydrophobia.) 



Capped Elbow. — This is an enlargement on the point 

 of the elbow, just behiad the shoulder, and on the side of 

 the chest ; sometimes it is in the form of a simple abscess, 

 (which see.) But the usual form is that of an encysted 

 tumor, or a fluid contained within a cyst of fleshy walla 

 which do not suppurate. 



