PARASITES OF THE EYE 177 



cular in its outer portion, with a surrounding area of 

 opacity, which was followed with a bluish-white opacity 

 of the whole cornea excepting the inner can thus. Under 

 treatment there was a general improvement, but a month 

 later there was a new attack, and five filaria were dis- 

 covered under the eyehds. The cornea became opaque 

 and permanent blindness ensued." 



In some cases there are no symptoms to indicate the 

 presence of the parasites. The only way to diagnose 

 the trouble is in finding the worms, and in many in- 

 stances this is not an easy thing to do, as they may be 

 concealed within the conjunctival folds, and are not 

 sufficiently active unless the surfaces are quite moist. 



Filaria Lacrimalis Bovis. — This resembles the worm 

 last described. The female is from 20 to 24 mm. in 

 length. It is usually found on the conjunctiva at the 

 inner angle. 



The symptoms excited by the presence of this para- 

 site resemble those last described — viz., a certain 

 amount of swelling of the lids, partial ptosis and lacri- 

 mation, together with inflammation of the conjunctiva 

 and cornea. 



The worm can readily be seen in motion on a moist 

 eye if carefully looked for. 



The Demodex folliculorum, commonly called the 

 "pimple mite," is often found in the miebomian glands 

 of the horse, dog, and sheep. As a rule it does not 

 cause any marked disturbance. 

 12 



