346 DISEASES OF CATTLE. 



circumstances the fungoid mass must be cut away and the wound 

 cauterized with the nitrate of silver, or else the eye will soon be 

 destroyed. Wlien ulcers of the cornea appear indolent, with a tend- 

 ency to slough, in addition to the treatment already prescribed, tonic 

 powders of copperas, gentian, and ginger, equal parts by weight, 

 should be given twice a day, mixed w4th the feed; dose, one table- 

 spoonful. 



STAPHYLOMA. 



This is a disease of the eyeball, in which the cornea loses its trans- 

 parency, rises above the level of the eye, and even projects beyond the 

 eyelids in the form of an elongated, whitish, or pearl-colored tumor, 

 which is sometimes smooth, at other times uneven. 



Causes. — Inflammation is the only known cause, although it may 

 not occur immediately; it frequently follows catarrhal conjunctivitis 

 and keratitis as a sequela. 



Treatment. — In a few cases restoration of sight may be effected by 

 puncturing the projecting tumor and treating it afterwards with 

 nitrate of silver in the same manner as prescribed for ulceration of 

 the cornea. In some cases spontaneous rupture has occurred, and 

 healing without any treatment at all. 



CATARACT. 



In cataract the crystalline lens becomes opaque and loses its trans- 

 parency, the power of refraction is lost — the animal can not see. 



Causes. — Cataract generally arises from a diminution (atrophy) 

 or other change in the nutrition of the lens ; it may occur as a result 

 of inflammation of the deep structures of the eye. Cataract may be 

 simple, or complicated with amaurosis, adhesions, etc. 



Symjjtoms. — It is known by the whiteness or loss of transparency 

 of the lens, although the pupil dilates and contracts. Sight ma}' be 

 totally lost; however, evidence is usually manifested that the animal 

 distinguishes light when brought out of a darkened stable. For the 

 most part the formation of cataract takes place sloAvly, the cases in 

 which it originates very quickly being but few. 



Treatment. — There is only one method for the treatment of cata- 

 ract — a surgical operation for the removal of the lens; but this is not 

 advisable, for the sight can not be perfectly restored, and objects 

 would be seen imperfectly without the aid of glasses. 



AMAUROSIS. 



This is a paralysis of the nerve of sight or the expansion of the 

 retini. 



Causes. — This is the result of concussion from a blow upon the 

 forehead, fracture of bone over the eye (causing downward pressure), 



