576 DISEASES OF THE HORSE. 
this time the wasting has been steadily progressive, especially of the 
muscles of the back and those surrounding the hip joint and the 
glutei. : 
Toward the termination of the disease it will be noticed that an 
animal is disinclined to move, and when made to do so there is 
manifest loss of power over the hind quarters, somewhat simulating 
a slight partial paralysis, and the hind quarters of the animal reel 
from side to side. In connection with this it may be noted that 
frequently there is paralysis of the sphincter ani and a dilated 
condition of the anus. These symptoms taken together point to some 
interference with the normal functions of the spinal cord in the lower 
dorsal and lumbar regions, and are probably owing to pressure 
caused by an exudation within the spinal membranes, In many 
cases shortly before death the heart’s action becomes exceedingly 
violent, shaking the whole frame at each beat, so that the sound can 
be heard at some distance from the animal. In some of these cases 
the animal may suddenly drop dead; in others the emaciation and 
weakness become so pronounced that it falls to the ground, and, 
after a short struggle, succumbs to the disease. In other cases, 
again, the animal falls to the ground and appears to be suffering 
from acute pain, struggles violently, sweat covers the body, and res- 
piration is very hurried. The struggles soon exhaust the patient’s 
strength, and for a time it lies quiet; soon, however, the struggles 
commence again, continuing until death occurs. In some cases the 
appetite is voracious. 
The symptoms of the disease as observed in experimentally inocu- 
lated animals are as follows: Twenty-four hours after the subcutane- 
ous injection of a small quantity of surra blood, in the great majority 
of cases, a small circumscribed and somewhat raised swelling is 
noticed at the seat of the inoculation. After forty-eight hours the 
tumor has increased in size and is accompanied with some edema; it 
presents a certain amount of tension of the parts involved, and is 
generally tender on manipulation. These conditions continue to in- 
crease, until by the fourth day the tumor may measure 3 or 4 inches 
in one direction by 2 or 3 in the other, and raised to the extent of an 
inch or an inch and a half above the surrounding tissues, or in some 
cases the tumor presents an almost circular form throughout. It will 
be also found that, if the tumor is firmly grasped, it is not fixed, but 
can be lifted up from the subcutaneous tissue. According to the 
nature and quantity of the inoculated blood, these symptoms rapidly 
present themselves, and either attain a maximum or are retarded 
until, varying from the fourth to the thirteenth day, the tumor at 
the seat of inoculation will be found to have lost a certain amount 
of its tension and tenderness. From this date the swelling and 
edema gradually begin to grow less, until finally, after a period of 
