KERATITIS CONTAGIOSA IN CATTLE. 
2 7 
bre and number of the neoplastic vessels, with a clearance of the 
cornea at its peripheries, which slowly but surely extends toward 
the centers, until the entire organ is again as transparent as could 
be desired. Where there has been^a rupture and the cavity caused 
thereby filled by granulation tissue, the same process occurs, 
and the same phenomena are seen, the vascularization decreasing, 
and the granulation tissue becoming more and more anaemic and 
less and less prominent, until it finally entirely disappears, its 
place being at first represented by a yellowish white, then white, 
and finally opaque pearly spot, which eventually disappears en¬ 
tirely, epithellium having again completely covered the spot, and 
restitution' is perfected in a manner seldom if ever seen in any 
process of wound healing where the previous lesions have been of 
such apparent severity. 
I will here remark that all these conditions have been followed 
step by step by microscopical studies made upon eyes removed at 
every distinct phase of the disease, but that it is my purpose to 
reserve their description for another paper, as well as some re¬ 
marks as as to a micro-organism present in the tissues. Cultiva 
tion attempts have thus far been futile, however. 
Nature .—The extremely slow manner in which this disease 
extends over a herd of cattle has been previously mentioned. No 
less remarkable has been the (in my experiments) absolute impossi 
bility of intentional transmission of the disease from afflicted to 
healthy animals. For example, completely sterlized plugs of ab¬ 
sorbent cotton were placed in the conjunctival sack (of a bull re¬ 
cently affected, but with a very profuse discharge) until completely 
saturated ; in one case such plugs were placed within the same 
sack of the eye of a healthy calf, while in another the cornea had 
been previously scarified with a sterlized lancet; notwithstanding 
the lids were held closed for five minutes in each case by atten¬ 
dants, the results were absolutely negative. The aqueous humor 
of the eye of a diseased calf having been withdrawn with a ster¬ 
lized syringe, was injected into the anterior chamber of the eyes 
of a rabbit, and, as well as possible, into the tissues of the cornea 
of another, with the same unsatisfactory results. They do not, 
however, have any value as evidence against the conclusion that 
