SCLEROSTOMA TETRACANTHtJM. 
571 
parasite (sclerostoma tetracanthum) occurring - as a coinci¬ 
dence in some horses affected with rabies. On post mor¬ 
tem, he found a great number imbedded in the mucous 
membrane of the colon and cascum, as well as a large num¬ 
ber free in the intestinal canal. He also, in the same arti 
cle, quotes a letter received of Dr. T. S. Butler, then of 
Iowa, in which he refers to the same parasite as existing in a 
number of horses, one oE which, a four-year-old mare, died 
from their effects, and on post mortem he also found a vast 
number infesting the mucous membrane, and a careful esti¬ 
mate indicated that there were not less than seventy-five 
thousand of these parasites infesting the large intestine of this 
animal, and this notwithstanding that the animal had passed 
in the fasces, during the two weeks preceding death, an 
squally large number. In the intestines were also found 
many of the large, white worms mentioned by Prof. Williams, 
and measuring from one to two inches in length. Williams 
also mentions this worm as existing in the mucous membrane. 
In the same subjects he found others in the intestinal canal, 
which were from two or three inches long, and he was of the 
apmion that these were of a different variety. There were 
lone of the white worms found in the intestines of any of 
hose cases examined by me, and, as stated before, I found no 
worms of any kind encysted in the mucous membrane of the 
:olon or caecum. 
From some experiments performed by Dr. T. S. Butler 
vith these small, red worms, mentioned in the letter referred 
o above, he succeeded in growing them to double their 
original length, during which time they lost the red color and 
>ecame much like the white worms which he found. As the 
esult of this, he was led to believe that probably the white 
vorm was only an advanced stage of the small, red worm. 
Colts seem to be more susceptible to the attacks of these 
yorms than older horses. This, perhaps, is due to the fact 
hat the intestinal walls are more delicate and consequently 
'ffer less resistance to the burrowing of the parasite in the 
rst stage of its development. In only two instances have I 
observed these worms in adult horses in any great numbers. 
