96 



PROCEEDINOS OF THE NATIONAL MUSEUM. 



VOL. 50. 



i 



nication with a large vesicle which is very prominent as a result of 

 its refractive appearance. The mouth has three lips. The esopha- 

 gus, including the bulb, is a fifth of the length of the body in the 

 male and a sixth in the female ; it is encircled by the nerve ring at 



the union of the 

 anterior and mid- 

 dle thirds. 



Male 2 mm. 

 long with a maxi- 

 mum thickness of 

 180 pi.. Body com- 

 monly curved in 

 an interrogation 

 mark. Esopha- 

 gus, including the 

 esophageal bulb, 

 430 |JL long. Ex- 

 cretory pore 50 ji. 

 posterior of the 

 esophageal bulb. 

 Two straight lat- 

 eral alae in the 

 region of the in- 

 testine and termi- 

 nating anterior of 

 the cloacal aper- 

 ture (fig. 119). 

 The cloacal aper- 

 ture is in the cen- 

 ter of a conical 

 eminence. The 

 tail is short, 130 

 [JL long, and termi- 

 nates in a dorsal 

 point 70 \i long. 

 Posterior of the 

 cloacal aperture are two straight caudal alae, sustained by a pair 

 of large stalked papillae; the caudal glands open just anterior 

 of these papillae. There are also a pair of sessile preanal 

 papillae and a pair of sessile adanal papillae. The spicule is 84 a long 

 and slightly curved. The gubernaculum (fig. 120) is 55 fi long and 

 terminates at its distal extremity in a hook like the barb of a fishhook. 

 On the ventral surface of the body there are two large cuticular 

 bosses on which the cuticular striae are especially prominent; the 

 more anterior of these is in the middle of the body, and the other one 



Fig. 118.— Oxturis pallarti. 



Male. 

 1915a. 



Enlarged. After Seurat, 



