NEMATOIDEA. 



45 



Genus Tricocephalus. 



In the worms which constitute this genus the 

 body is very long, and is composed of two portions ; 

 of these, the anterior portion is filiform, very narrow 

 in front, and longer than the posterior portion, which 

 is proportionately much broader, and which contains 

 the reproductive organs and the whole of the 

 intestinal tube with the exception of the oesophagus. 



The Tricocephali are found, in the coecum, or some 

 other part of the large intestines of man, and of the 

 mammiferse. 



The species which is found in man is the 



Tricocephalus Dispar. 



In this entozoon ^^g- ^^-^ 



the integument is 

 striated transversely, 

 with the exception of 

 a longitudinal band 

 which is thickly stud- 

 ded with minute 

 papillae ; the neck is 

 very long, and like a 

 fine hair in appear- 

 ance. The posterior 

 part is rolled up in the male, which is much smaller 

 than the female, in which the posterior part is usually 

 enlarged, and straight. 



^ Figure 10. The Tricocephalus dispar. — 1. The male, of the 

 natural size. — 2. The female of the natural size. — 3. The head 

 magnified. — 4. The tail also greatly enlarged. 



