42 VETEEINAEY OPHTHALMOLOGY. 



stretch. Bring the knife straight up and down and 

 cut the whole length of the canaliculus. This is diia- 

 cultof accomplishment in the horse, owing to the length 

 of the canal ; but a knife with a malleable shank will 

 facilitate matters much. Remember and divide the 

 canaliculus close to the juncture of skin and mucous 

 membrane, so that its function of collecthig the tears 

 may be as little interfered with as possible, close 

 coaptation to the conjunctiva being one of the factors 

 of that important function. 



Strictura of the Lachrymal Duct.— Most common of 

 all the lachrymal affections. Its one symptom is a 

 flowing of tears— Epiphora. May be result of catarrh, 

 trauma, carious teeth, pressure from tumors, and peri- 

 ostitis. 



Dacryocystitis Catarrhalis. — Seldom recognized be- 

 fore the chronic stage. Practically no difference be- 

 tween this and catarrh. Will find a swelling at the in- 

 ner angle of the eye, caused by a retention of secretion 

 from the catarrhal inflammation, and swelling, lessening 

 the caliber of the excretory ducts. Firm pressure on 

 this swelling will cause mucous to flow from either 

 the canaliculus or down the duct, into the nasal cavity. 

 The swelling is generally painless. Keeping the sac 

 empty affords some relief. Have generally a coexist- 

 ing blepharitis marginalis. The secretion after a time 

 becomes irritating, and this is especially the case when 

 it is permitted to remain quiet some time in the sac. 



