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the pupils suddenly eontraot, and then dilate and contract alternately 

 nntil tliej^ adapt themselves to the amount of light. The horse does 

 not swerve Avhen a feint to strike is made unless the hand causes a 

 current of air. The ears are held erect and turn quickly toward any 

 noise, and the horse steps high to avoid stumbling over objects which 

 it can not see. 



Treatment is only useful when the disease is symptomatic of some 

 removable cause, like congested brain, loaded stomach, or gravid 

 womb. When recovery does not follow the termination of these con- 

 ditions, apply a blister behind the ear and give one-half dram doses 

 of nux vomica daily. 



TUMORS OF THE EYEBALL. 



A variety of tumors attack the eyeball — dermoid, jDapillary, fatty, 

 cystic, and melanotic, but perhaps the most frequent in the horse is 

 encephaloid cancer. This may grow in or on the globe, the haw, the 

 eyelid, or the bones of the orbit, and is only to be remedied if at all 

 by early and thorough excision. It may be distinguished from the 

 less dangerous tumors by its softness, friability, and great vascularity, 

 bleeding on the slightest touch, as well as by its anatomical structure. 



STAPHYLOMA. 



This consists in a bulging forward of the cornea at a given point 

 by the saccular yielding and distension of its coats, and it maj^ be 

 either transparent or oj^aque and vascular. In the last form the iris 

 has become adherent to the back of the cornea, and the whole struc- 

 ture has become filled with blood-vessels. In the first form the bulg- 

 ing cornea is attenuated ; in the last it may be thickened. The best 

 treatment is by excision of a portion of the iris so as to relieve the 

 intra-ocular pressure. 



PARASITES IN THE EYE. 



Acari in the eye have been incidentally alluded to under inflam- 

 mation of the lids. 



The Filaria lachrymalis is a white worm, one-half to 1 inch long, 

 which inhabits the lachrymal duct and the under side of the eyelids 

 and haw in the horse, producing a verminous conjunctivitis. The 

 first step in treatment in such cases is to remove the worm with for- 

 ceps, then treat as for external inflammation. 



The Filaria papiUosa is a delicate, white, silvery-looking worm, 

 which I have repeatedly found 2 inches in length. It invades the 

 aqueous humor, where its constant active movements make it an 

 object of great interest, and it is frequently exhibited as a "snake in 

 the eye." It is found also in other internal cavities of the horse, to 

 which it undoubtedly makes its Avay f rom the food, and especially the 



