WATSONIUS 



33 



in West Africa, in Northern Nigeria, and is said to be a 

 common parasite in Bornu and the neighbourhood of 

 Lake Chad. According to Blair, considerable anaemia 

 and debility is caused by this parasite, and not infre- 



ph.p. 



FIG. 17. Watsonius voatsoni. (After Shipley.) ph.> pharynx ; ph.p., 

 pharyngeal pouch ; sph., sphincter ; s.v., seminal vesicle ; y.g., yolk glands ; 

 v.d., vas deferens ; /., uterus ; al.c., alimentary canal ; /., testes ; y.r. t yolk 

 reservoir ; sh.g., shell glands; oo., ootype ; ov., ovary; L.c., Laurer's canal. 



quently death results. The testes are lobulated, elongated, 

 and are pressed close against each other. The ovary is 

 round and is posterior to the testes. The anterior or oral 

 sucker is very small, hardly a definite sucker (fig. 17). 



3 



