THE NERVOUS SYSTEM 383 



than usual, and at the first glance it seems a beautifully developed 

 eye. When it occurs, both eyes are affected, as a rule. In the 

 majority of cases the horse carries his head well up, and steps very 

 high, in a hesitating, jerky manner. On carefully examining the eye, 

 the pupillary opening is found very much dilated, and instead of being 

 elliptical, it is nearly circular, very little of the iris being seen ; 

 whilst on being subjected to the rays of a strong light, the pupil will 

 not contract. Detection of amaurosis is really of more importance in 

 examination for soundness than that of cataract. 



643. Filaria Oculi, or worm in the eye, is extremely rare in this 

 country, but is frequently seen in hot climates — e.g., India, The 

 parasite is the Strongylus filaria, and measures from \ to 1 inch 

 long ; it is found in the anterior chamber of the eye, where it moves 

 about freely, setting up irritation, and giving to the aqueous humour 

 a peculiar milky hue. It can be successfully removed by casting the 

 horse, and cutting into the eye at the upper edge of the cornea, so 

 liberating the humour, and with it the offending worm. 



644. There are several other diseases of the eye, such as nebula, 

 glaucoma, staphyloma, tuberculosis, etc., but as they are of rare 

 occurrence, I will not dwell upon them. 



645. Dislocation of the Eyeball, a displacement of the eyeball, 

 mostly seen in the dog, as a result of fighting. When recently 

 done it is readily reduced, by pressing it carefully back into the 

 socket with the thumbs, pulling the lids forward with a pair of 

 forceps, and keeping it in its place with a bandage and a pad of wet 

 lint. When it has been displaced for some time, and has become 

 swollen and congested, it should be bathed well with tepid water or 

 an infusion of poppy heads ; and it may be necessary to slit the 

 eyelids at the outer corner before returning it ; then it should be 

 maintained in its place by one or two stitches of antiseptic thread, all 

 being covered with a lint pad made wet with boracic lotion (par. 1069, 

 No. IV.), and secured in its place with a bandage. In some cases the 

 eyeball is so much damaged that it has to be removed. 



