FLATWORMS, ROUKDWORMS, AND ROTIFERS 



67 



another animal. As seen in tlie mature stage in tlie diges- 

 tive tract of man, tlie tapeworm has a head about the size 

 of the head of a pin. The cro^vn of this tiny head is beset 

 with manjf minute hooks 

 and the sides of the head 

 are furnished with suckers 

 (Fig, 33). All of these 

 are for attachment to the 

 host. The head is fol- 

 lowed by a very short, 

 slender neck. The body, 

 from the neck on, has a 

 jointed appearance owing 

 to its being divided into 

 jomtlike divisions called 

 proglottids. The body 

 varies from twelve to 

 twenty-four feet in length 

 and from one quarter to 

 two fifths of an inch in 

 mdth, but is thin and 

 tapelike, hence its name 

 (Tig. 34). About half, 

 and sometimes more, of 

 the proglottids are ca- 

 pable of producing eggs. 

 When the terminal pro- 

 glottid becomes gorged 



•ii • i- T, „„!-„ „T,T.TrT Fig. 34. — Adult tapeworm ; o, head. 



^\ath eggs, it breaks awa}' f , . 



from the others and passes out of the host's body. The 

 succeeding terminal proglottid, in time, does the same 

 thing and is followed by others untU many segments full 



