ZOOLOGY FOR MEDICAL STUDENTS 



CHAP. 



i So 



B very primitive kind of nerve, as it passes straight to 

 t he do- ntral line and forms a direct bridge connecting the 



udinal IKTVC trunk with the myo-epithelial cell. 



axis of the body is the alimentary canal which is very 



simpk in structure in correlation with the fact that the Ascaris lives 



,,1-matcruil which is digested for it by its host. The mouth 



t 



int. 



ex. 



m.e. 



tit 



otr. 



Ascaris (9), transverse section, c, Cuticle; d.l, dorsal line; ep, epidermis; ex, excretory tube ; 

 : .1 line; m.e, myo-epithelial cell; od, oviduct; ov, ovary; t, tail of myo- 

 :, vnitr.il line. 



i- a small pore at the tip of the body, surrounded by three 



roundish lobes arranged like a trefoil, one lobe being dorsal and the other 



ntral. The mouth leads into a short pharynx with thick walls 



and this in turn kads into the thin-walled intestine which passes without 



ins a trans verse slit on the ventral side close to the pos- 



nd of the body (Fig. 81, an). The wall of the intestine (Fig. 82, int) 



