PARASITES OF ANIMALS. 137 
also in the arteries of the colon, cecum, small intestine, and 
liver, as well as in the posterior mesenteric and renal arteries, 
and others adjacent to the intestine. These tumors are gen- 
erally fusiform, and as large as a man’s finger; but they are 
sometimes globular, and may become as large as a man’s 
head. The middle membrane of the artery in these dilations 
becomes enormously thickened, sometimes being twelve times 
“as thick as in the healthy artery. In old tumors various hard 
or calcareous deposits often take place in the thickened walls 
or in the inner membrane; and in such cases, the walls being 
weakened, are liable to be ruptured by some unusual exertion 
of the animal, when death results almost instantly. In the 
interior of the aneurism there is generally a deposit of fibrin, 
firmly adherent to the inner surface. In this and in the dif- 
ferent layers of the walls the worms are found, — sometimes 
only a few, but frequently large numbers. This disease is 
very prevalent among old horses. In France, as many as 
ninety-six out of one hundred have been found affected with 
the disease. 
I am not aware that any remedies have ever proved useful. 
Generally it would be impossible to detect the disease during 
life, unless the tumors became very large. 
Selerostoma pinguicola Verrill. 
On two occasions I have received specimens of a rather 
large parasitic worm, which lives in the fat of hogs. In the 
first case, five specimens were obtained, at New Haven, by 
Dr. M. C. White, from the fatty portion of a spare-rib ; in the 
second instance, at Middletown, Conn., Dr. N. Cressy found 
large numbers of the worms in the fat about the kidneys of a 
young Suffolk pig, brought from New Jersey. Un- 
fortunately, none of these specimens are in so good a state 
of preservation as to enable me to determine with certainty 
all the points of their structure. Those which I owe to the 
kindness of Dr. White, had been mounted in glycerine: as 
microscopic objects and pressed out flat, before they came 
into my possession, and the tissues were thus injured and 
the organs deranged. Those from Dr. Cressy, were both 
pressed flat and drieds,.etuby.paretul masceration, and 
with much labor, I believe that most of the important char- 
