178 OPHTHALMOLOGY FOR VETERINARIANS 



The Trombidium, an extremely small silky worm, 

 invades the margin of the lids of the dog. Its more com- 

 mon site is at the outer and inner canthi. The symptoms 

 produced^ by this are not marked. 



The Trichina is said to have been found in the muscles 

 of the eyelids, as well as in other muscles of the body. 

 They cause swelHng of the Hds which is usually pain- 

 ful, conjunctivitis, etc. The general symptoms of 

 trichina are also present. 



The Hemopis sanguisuga, the horse leech, has been 

 found clinging to the Hds and conjunctiva of the horse 

 under favorable conditions. 



Parasites Found Within the Eyeball.— The Filaria 

 oculi equina, also known as the Filaria papulosa and the 

 Filaria pellucida. This is not infrequently seen in the 

 eye of the horse. It was known as early as the seven- 

 teenth century, and has been discovered by various 

 observers in this country and in Europe. 



It seems to be more prevalent among animals which 

 are allowed to graze in wet pastures in moderate cli- 

 mates. 



It is described as a thread-like worm, from 22 to 35 

 mm. long, the male being the longer, with spiral tail, 

 and reddish- white in color. 



Law describes the symptoms as follows: ''Exception- 

 ally the worm causes no inflammation, and it can be 

 seen actively bending and unbending itself in the form 

 of a loop, a figure-of-eight, or a spiral, in the anterior 



