VETERINARY OPHTHALMOLOGY. 71 



burst and leave a ring ot ulcers. A triangular net- 

 work of vessels will be seen running toward phl^^c- 

 tenule, its base towards the retrotarsal fold and its 

 apex at the phlyctenule, if this is at the edge of the 

 cornea. If, however, the phlyctenule lies some distance 

 from the corneal border, the apex of the triangle 

 appears cut off at the edge of the cornea, thus leaving 

 a space of clear tissue intervening between it and the 

 phlyctenule. If the attack is severe, vascular keratitis 

 may supervene, vessels then would extend upon the 

 cornea quite up to the phlyctenule. The secretions 

 from the eye irritate and excoriate the parts over which 

 they flow. 



Interstitial Keratitis. — Also termed Parenchymatoxis 

 and Difficse. Will have swelling and diffuse cloudi- 

 ness, which cloudiness usually extends from margin 

 to center, and very rarely the reverse. May be very 

 sliglit, and again may be very dense, simulating ground 

 glass. May be irregular in density, causing white and 

 grayish patches. The corneal surface usually loses its 

 polish and assumes a dull stippled appearance, due to 

 loss of epithelium. Vessels may appear in the corneal 

 substance, running from margin toward center, and are 

 sometimes numerous enough to cause a bright red re- 

 ilex. Happily, there is very little tendency toward 

 ulceration. This form is tedious, taking months to 

 cure. 



Suppurative Keratitis. — The inflammatory infiltra- 



