PARASITES OF ANIMALS. 73 
tained embryos, which are very different from both the old 
worm and the measle-worm. They are provided with six 
hooks or spines, placed in three pairs upon the head. By 
means of these they quickly bore their way through the walls 
of the intestine into the blood-vessels, and are thus carried to 
all parts of the body. They finally lodge in various organs, 
but especially in the muscles, liver, brain, eyes, lungs, and 
heart. They then excavate galleries for themselves in these 
situations, causing, if in large numbers, a great amount of 
inflammation and disease, which in some cases proves fatal. 
The inflammation soon causes cysts to be formed around the 
intruders, by which they are enclosed and restricted in their 
motions. Thus the ‘“‘ measles” in the muscles of hogs and 
man are formed. After this the patient may recover, unless 
these parasites have lodged in the brain or other vital organs, so 
as to produce serious symptoms subsequently. In the human 
subject more than 100 cases have been recorded in which 
these parasites have taken up their abode in the brain, causing 
epilepsy, insanity, and sometimes sudden death. In such 
cases, which are probably more common than is generally im- 
agined, there can be norelief. There have also been recorded 
quite as many instancesin which these cysticerc? or larval tape- 
worms have been situated within the ball of the eye, causing 
a partial or total loss of sight, and somctimes great inflamma- | 
tion. Many of these have been successfully removed. In 
other important organs they are liable to produce serious 
trouble. But when in the subcutaneous, areolar, or inter- 
muscular tissues, they may often be easily removed by the 
surgeon. In hogs they are much more liable to produce these 
results, because hogs are likely to swallow whole joints, or 
even entire tape-worms, while human beings seldom swallow 
more than a few dozens of eggs. 
The effects and symptoms caused by the adult tape-worms 
are discussed under the next species, together with the 
remedies. 
As means of prevention every one should avoid eating pork, 
in any form, that has not been thoroughly cooked. In this 
way it is easy to avoid the mature tape-worm of this species. 
10 Digitized by Microso: 
