WHAT MAY CAUSE TAPEWORM. 



329 



flesh. The eggs of the worm are taken up by the pig iu 

 its search for food here and there, especially among dung 

 heaps and other filth. The worm is nearly spheroidal in 

 shape, having an average diameter of about l-694th of an 

 inch, and therefore readily enters the circulation, whence 

 it is carried to various parts of the body. It is very pro- 

 lific. It lives about two years and produces at least 1,600 

 joints, each of which contains 53,000 eggs — total, 85,000,- 

 000. Fortunately, like the ova of other parasites, many 

 are destroyed in various ways. 



After the ova enter the flesh, several changes occur. 

 The germs are inclosed in small cysts or bladders, each 



F\g. 165. Larva of Pork Tapeworm, Fig. 166. Head of Taenia Solium 



with caudal vesicle, liberated or Pork Tapeworm. 



from cyst. Hooks at top. 



having a small, rudimentary head, with hooks and suck- 

 ers, &c. They remain in the body till the pig is slaugh- 

 tered, when, if the pork is not thoroughly cooked, they 

 produce full-grown tapeworms. An unusually large num- 

 ber of them may kill a hog. They are peculiar to the 



