232 



ZOOLOGY 



SECT. 



wall of the intestine is slight and temporary ; it is effected by 

 certain organs of adhesion, the hooks and suckers 011 the head. 



The head (Fig. 181) maybe roughly described as pear-shaped, but 

 becomes four-sided at the broader end. In the middle of this 



Fie. ]>:(>. Tsenia solium. Entire specimen, reduced ; cap. head. (After Leuckart.) 



broader, anterior end is a rounded prominence, the rostellum, round 

 the base of which there is a double row of usually about twenty-eight 

 curved and pointed chitinous hooks. The rostellum is capable of 

 being protruded and retracted to a slight extent, and the position 



