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PROCEEDINGS OF THE NATIONAL MUSEUM. 



VOL. 50. 



Externo-dorsal ray very slender. No median dorsal ray. Each 

 dorsal lobule of the bursa is sustained by a ray whose base is united 

 with the base of the externo-dorsal ray, somewhat thicker than the 

 latter, with somewhat bifid tip. Spicules (figs. 168 and 169) slender, 

 equal, about 1 mm. long, united by a membrane in the posterior two- 

 thirds, more closely toward the tip, where the membrane forms a 

 spatulate enlargement. Prebursal papillae small, inconspicuous. 



.^■m-l- 



V 



167. ' 168. 



FiGs.167, 108.— Nematodirusspatiiiger. 167, Anterior extremity of body. X 150. After Ransom, 

 1911. 168, Posterior extremity of male, ventral view, d., Dorsal ray; e. d., extekno-dorsal 

 ray; e. I., externo-lateral ray; I. v., latero-ventral ray; to. I., medio-lateral ray; p. I., 

 postero-lateral ray; sp., spicules; v. v., ventro-ventral ray. x 150. After Ransom, 1911. 



Female 12 to 20 mm. long Avitli a maximum thickness of 200 to 

 250 II at the vulva. Thickness suddenly reduced just behind the 

 vulva. Tip of tail truncate, bearing a short, slender, acutely pointed 

 bristlelike process (fig. 170) . Anus 70 to 80 ii from the truncated end 

 of the body. Vulva a transverse slit located about one-third the 

 length of the body from the posterior end. Combined length of the 

 muscular portions of the two ovijectors (fig. 171), including the 

 sphincters, about 400 [;.. Eggs oval, 175 to 200 \^ long by about 100 \}. 

 wide. Embryos develop into filariform larvae before hatching. 



Hosts. — Ctenodactylus gundi. Commonly a parasite of ruminants. 



Location. — Small intestine. 



