362 DISEASES OF CATTLE. 



protrude out between the eyelids, giving the animal the appearance of 

 1 laving a double eyelid. 



Treatment. A surgical operation becomes necessary for their removal, 

 one requiring a skilled operator. 



STRABISMUS SQUINTING. 



This is a very rare affection among cattle. Strabismus may be either 

 single or double affecting one eye or both. It is due to a paralysis, or 

 a weakening of one of the straight muscles of the eyeball. Generally 

 it is a congenital defect, and the squinting is to wards the nose strabis- 

 mus convergens. It is best not to attempt to remedy the defect, as the 

 risk in an operation is greater than the chances of success warrant. 



PTERYGIUM. 



This term is applied to a fleshy-colored membrane, triangular in form, 

 which most frequently grows from the inner angle of the eye and extends 

 over the cornea, thus interfering with vision. It may grow from the 

 outer angle, or even from the superior or inferior hemisphere of the 

 eyeball. The figure is invariably that of a triangle, with its base on 

 the white of the eye, and its apex more or less advanced over the cor- 

 nea toward its center. 



The distinguishing characteristics are the constancy of the triangular 

 form, and the facility with which the whole of it may be taken hold of 

 with a pair of forceps and raised into a fold on the cornea. Every 

 other kind of excrescence attached to this membrane continues firmly 

 adherent to it, and can not be folded and raised from the surface of the 

 cornea in any manner whatever. 



Treatment. Raise the fold and dissect it away from all points of 

 attachment. 



TRICHIASIS INVERSION OF THE EYELASHES. 



In the simplest form the eyelashes bend inwardly, touching the eye- 

 ball, causing irritation and simple conjunctivitis. It may be also asso- 

 ciated with entropion. 



Treatment. The offending eyelashes should be cut off or pulled out. 

 In cases where the natural growth of the eyelashes is directed inward 

 an operation similar to that for entropion becomes necessary. 



ENTROPION INVERSION OF THE EYELID. 



In inversion of the eyelid the eyelashes soon irritate the anterior 

 face of the cornea, and produce more or less inflammation and opacity. 

 The inversion may be due to the growth of a tumor within or without 

 the lid, to abscess, laceration, or injury, causing the lid to lose its nat- 

 ural conformitj 7 to the eyeball, ulceratious, etc. Surgical interference, 

 in either case, becomes necessary to restore the lid to its natural direc- 

 tion. 



