DISEASES OF THE EYE. 523 



VTI. Cataract. 



As the most common termination of all inflammatory diseases of the 

 eye, we see a white opaque substance covering the lens, and oftentimes 

 completely filling the pupil. This is cataract, of which there are two 

 kinds, distinguished by the terms capsular and lenticular, according to 

 their position. Cataract is organized lymph attached to the lens. 



How to know rt. — Usually the pupil is very much dilated, and filled 

 with the white lymph, the defect being so plain as to be seen a hundred 

 feet away. Sometimes, however, it can only be detected by a close ex- 

 amination. Examine the horse, first, in strong sunlight, and note carefully 

 the degree of contraction of the jDupil ; then place him in a dark stall, and 

 examine the eye with a candle. A healthy eye reflects three candles, 

 the first from the cornea, the second from the surface of the lens, the 

 third from the back of the lens. When either or both of the last two are 

 blurred or, worse, entirely wanting, you need no further proof of the 

 existence of cataract. 



What to do. — III recent cases, the eye may sometimes be cleared up by 

 simply giving a purgative. No. 23, and applying a lotion. No. 82, at the 

 same time giving No. 66, internally ; but in later stages nothing could 

 avail except to dissect them out — an operation that is never practiced on 

 the horse for the reason that, without glasses, he would never be able to 

 see things again, in their right position, size and form. 



A FREQUENT RESUl^i OJ< IMPERFECT VISION. 



Imperfect vision is worse than blindness, bemg vastly more misleading 

 and wholly unreliable. 



Vlli. Filaria Oculi, or "Worm in the Eye. 



This is a small, thread-like worm, seen floating about in the aqueous 

 humor in the anterior chamber of the eye. It is very rare. The worm 



