746 
REPORTS OF CASES. 
charge from left nostril; teeth were in good condition; no 
enlarged glands in the intermaxillary space. There was no 
enlargement over the sinuses, but, on percussion over the left 
side, dullness was heard. A diagnosis of pus in the sinuses 
was then made, and the operation of trephining was recom¬ 
mended. 
The mare was kept two or three days before being oper¬ 
ated upon, and in that time there was a perceptible increase 
in the size of the face over the sinuses of the left side, although 
there was no increase in the amount of the discharge. This 
aroused suspicion, because it was not likely that the simple 
accumulation of pus, that had an avenue of escape, would 
cause such a rapid and well marked enlargement. Because 
of this fact it was surmised that a tumor of some kind was the 
cause of all the trouble. 
The mare was prepared in the usual way, by having 
nothing to eat for breakfast, and one ounce of chloral hy¬ 
drate. She was then cast and secured. A V-shaped incision 
was made over the supermaxillary sinuse, the skin dissected 
back and periosteum treated in the same way; then by the 
trephine a circular piece of bone was removed. By doing 
this another exit for the escape of the contents was made. 
Here again we were led to believe, more and more, that a 
tumor existed instead of a simple collection of pus, for as the 
bone was removed only a very small quantity of pus escaped, 
and then, by introducing the finger, our diagnosis was con¬ 
firmed, for then we could feel the thickened mucus membrane 
lining the cavity, and here and there scattered over the mem¬ 
brane we could feel more or less large granulations. We at 
once saw that it would be useless to continue to treat the ani¬ 
mal, for how could we successfully remove those granulations 
which were undoubtedly the cause of all the trouble? The 
owner was informed as to her condition, and when told that 
we could do nothing for her, he gave his consent to have her 
destroyed. This was done and the head removed. After 
carefully chiselling away the external wall of the supermax¬ 
illary sinuse we could thoroughly examine the contents. 
Some of the granulations were as small as a pin’s head, and 
