CASES OF EMBOLISM OF THE POSTERIOR AORTA. 
5 
posterior to this the embolism is of a redder color, indicative of 
a more recent formation. 
The external iliac, near its origin, contains a large clot of 
thick syrupous fluid, which is continued down into the femoral by 
an older deposit, and this is prolonged down into all the branches 
arising from that trunk by fibrinous deposits of a darker color and 
somewhat softer organization. The smallest arteries are plugged 
up with red clot. 
The muscular structure of the left leg is engorged, and the 
deep muscles have lost their dark red coloration; they have be¬ 
come pale, softer, and are maculated here and there by what 
seems to be an interstitial hemorrhage. 
The remainder of the body, as far as the post mortem exami¬ 
nation was carried, seemed to be perfectly healthy. 
The history of the second case is not less interesting or sur¬ 
prising, so far as the rapidity with which the symptoms exhibited 
themselves. 
This horse, as far as known, had never been sick or lame. 
One day, while in harness and returning from a drive, he sudden¬ 
ly became lame, and was with much difficulty returned to his 
stable. The next morning he was found perfectly well. A few 
days later he was returned to his work and behaved in the same 
manner, and then kept on this way for about three weeks. Or. 
Robertson saw him, and though he suspected lesions of some 
large arterial trunks of the right hind leg, he had no opportunity 
to make his diagnosis positive. 
At his suggestion the horse was brought to the College. As 
he arrived there, one morning, he presented the following con¬ 
ditions : His skin is profusely covered with cold perspiration; 
his countenance is very haggard; his nostrils dilated; his eyes 
staring ; his pulse is very fast, weak and irregular. The function 
of locomotion is very difficult, walking very painfnl, the lameness, 
being excessive, is located in the right hind leg. While at rest 
this is carried in abduction, and the seat of violent motions, 
spasmodic pains which the animal manifests by suddenly raising 
his leg from the ground, carrying it violently in abduction and 
