PARASITES OF THE ALIMENTARY TRACT 89 
times in pigs. The Cysticercus may be the size of a 
pigeon’s or hen’s egg, and is pedunculated, possessing a 
long, narrow neck or stalk, by which it is attached. 
This parasite has been responsible for fatal outbreaks 
of hemorrhagic hepatitis in lambs, owing to migration 
from the intestine, through the bloodvessels and liver, 
into the peritoneal cavity. The occasional presence of 
Fic. 24.—T#£NIA MarGINaTA. 
a, Head; b, unripe segments; ¢, ripe segments ; 
d, hook ; e, Cysticercus tenuicollis, 
small cysts in the muscles of the sheep has given rise 
to the term “‘ pseudo-measles of the sheep.” 
In pigs a similar condition is seen, particularly affect- 
ing the muscular pillars of the diaphragm. 
Tenia Echinococeus.—This is the smallest tapeworm 
of the dog, and never exceeds four segments. The head 
is armed with a double row of hooks, by means of which 
the parasite attaches itself to the mucous membrane 
