166 PARASITOLOGY. 
Animals Infested.—The ox, sheep, pig, etc. 
Parts Intested—Liver, sometimes the lungs. The 
writer has noted one case of Hepatic Distomiasis in 
apig; four specimens of the Distoma Americanus 
were found. 
Conditions Produced.—The larval fluke upon being 
taken into the stomach on grass is liberated by the 
dissolving of the gelatinous capsule enclosing it. 
It finds its way to the liver through the hepatic duct 
and finally becomes stationary in a small bile duct; 
or it may penetrate the duct and become lodged in 
Fig. 64—DisromMa AMERICANUS. 
a, Oral sucker. 
b, Ventral sucker, 
c, Intestine 
the tissue outside. It here forms acyst which varies 
in size up to a hen’s egg. The outer surface of the 
liver presents the appearance of black prominent 
elevations. Upon section of these tumefactions they 
are found to contain a cavity within, which is filled 
with a chocolate-colored fluid and some debris, and 
in the older cysts some earthy material. 
One or more flukes are found in each cyst. The 
portal lymph glands, that lie against the posterior 
surface of the liver at a point where the portal vein 
