442 



THE ANIMAL PARASITES OF MAN 



FIG. 319. (Esophagostomum stephanostomum var. thomasi. I, male, natural size ; 2, 

 female, natural size; 3, head of female, ventral view, showing cephalic vesicle and ventral cleft 

 limiting it behind, x 55 ; 4, head of female, dorsal view, x' 225 ; 5, head of male, end view, 

 showing external and internal leaf crowns, x 225 ; 6, tail of male, lateral view (cf. fig. 318, D), 

 X 20; 7, tail of female, lateral view, x 20 ; 8, CEs. thomasi, posterior ray of bursa, X 150 ; 

 9, CEs.dentigerum, from chimpanzee, posterior ray of bursa, x 150; 10, (Es. stephanostomum, 

 from gorilla, posterior ray of bursa, x 150. 



