DISEASES OF THE EYE. 117 



symptom of which is a persistent watering of the eye. Iniiammation fol- 

 lows this stoppage, resulting in an abscess, which bursting causes the 

 fistulous aperture fix)m which the name of the affection is derived. 



The treatment of this condition demands the sHll of an experienced 

 surgeon. 



^Affectioj^s of the Haw. 



In the inner comer of the eye is a semilunar fold of the mucous 

 membrane, the cavity of which is directed outwards. This is called the 

 membrana nictitans, and resembles somewhat the third eyelid in birds. 



The purpose of this structure is to protect the eye, and by it dust and 

 irritants are swept, as it were, from the eyeball. 



This membrane is subject to Inflammations resulting from injuries, irri- 

 tants, and possibly constitutional diseases. During the existence of an 

 inflammation the part becomes red and swollen, partially covering the 

 eyeball obstructing the sight, and giving rise to a profuse flow of tears. 

 Considerable pain often attends the affection, which if persistent may 

 result in a permanent enlargement of the membrane, and consequent 

 unsightly deformity, as well as becoming a source of inconvenience and 

 annoyance to the animal. 



Trealmenl. — The acute inflammation should be controlled by frequent 

 bathing and the use of the following.— 



R Zinci Sulph. gr.iij 



Aquffi Sij 



Ft. Mist. Sig. Drop into the eye three or four times daily. 



This astringent lotion or the use of borax and camphor water, ten grains 

 of the former to one ounce of the latter, will in nearly all cases prove 

 sufBcient; if not the membrane must be snipped with the scissors. 



