ASCARIS. 



235 



CHAPTER XXV. 



INTESTINAL PARASITES. 



IN connection with the examination of amoeba?, it is well to 

 be on the lookout for the commoner form of intestinal para- 

 sites which may be found. 



ASCARIS. 



Chief among them in frequency is the common round worm, 

 or Ascaris lumbricoides (Figs. 80 and 81). It is a cylindrical 



worm, pointed at both ends, 

 and of a color ranging from 

 yellowish to red. Near the 

 head is a constriction or 

 neck. The male is shorter 

 than the female, and curves 

 at the posterior extremity. 

 An adult worm possesses 

 transverse markings, and 

 four longitudinal bands ex- 

 tend from one extremity to 



FK4. 81. 



FIG. 80. 



Ascaris lumbricoides (von Jaksch): a, Worm, 

 half natural size ; b, head, slightly magnified; c, 

 egg (eye-piece I, objective 8 A, Reichert). 



Egg of the common ascaris 

 (Ascaris hvmbricoides) of man as 

 found in faeces. Seen with super- 

 ficial focus. Greatly enlarged. 



(Stiles.) 



the other. The female measures from 10-30 c.m. in length. 

 Its ova, which are numerous and which may be demonstrated 



