PARASITES OF ANIMALS. 85 
that are worth keeping, or are necessary, in order to expel 
their parasitic worms, of which there are generally many 
kinds. There are numerous drugs that are efficacious for this 
purpose, some of which are mentioned under the beef tape- 
worm (page 191). But the principal difficulty is this—those 
who keep the most dogs, the worst dogs, and the dogs most 
likely to harbor parasites in abundance, are the very persons 
who are least likely to adopt such measures, either not know- 
ing or not caring for the consequences. 
Tenia ceenurus Kuch., of the Dog; andits young, the “water- 
brain” of Sheep. 
In the substance of the brain of phoee there is often found 
a soft tumor, often as large as a pigeon’s egg, and sometimes 
larger than a hen’s egg, which is filled with a watery fluid. 
Such tumors would go on increasing in size indefinitely, until 
Figure 62. 
death ensues. But even long before the result becomes fatal, 
the health is seriously impaired. The brain is often found 
much diseased, and in part quite disorganized—a state of 
things which in man’ would produce incurable insanity. In 
sheep, it causes “ staggers,” “ gid,” “vertigo,” or “ sturdy,” 
and other cerebral derangements. This disease is, in most 
Figure 62.—Cenurus or water-brain of sheep. Natural size. Hearth and 
Home, after Thudichum. Digitized by Microsoft® 
