144 ALLAN HANCOCK PACIFIC EXPEDITIONS VOL.2 



communicates with the shallow buccal cavity. The anterior end of the 

 esophagus is rounded and extends into the buccal cavity. There are 

 two papillae near the anterolateral margin of each of the lips. Each 

 of the ventrolateral lips has two additional papillae situated near the 

 median anterior margin; these papillae could be seen distinctly in the 

 lateral view but were not apparent in the en face view. There is thus 

 a total of 10 papillae on the lips. The well-developed amphids terminate 

 near the median anterior margins of the ventrolateral lips. 



The excretory pore is ventral and prebulbar in both sexes, being 1.48 

 mm. in the male and 1.73 mm. in the female from the anterior end. The 

 pore communicates with an excretory vesicle which connects with the 

 excretory canals. The canals form an "X" where they lead to the vesi- 

 cle. The nerve ring is 0.258 mm. in the male and 0.263 mm. in the 

 female from the anterior end. The position of the nerve ring seems to 

 be quite constant, varying little in the specimens of different sizes. The 

 esophagus varies in length from 1.43 to 1.69 (average 1.55) mm. in 

 the male and from 2.01 to 2.13 (average 2.08) mm. in the female. Its 

 posterior end terminates in the subspherical bulb, which is equipped 

 with cuticularized valvular structures. There is a constriction, the isth- 

 mus, between the bulb and the anterior portion, or the corpus of the 

 esophagus. The rectilinear intestine is enlarged into a bulblike region 

 at its anterior end. 



Male: The body of the male ends in a ventrally directed, bluntly 

 rounded tail, which varies in length from 0.11 to 0.20 mm. Laterally the 

 tail is provided with wide caudal alae (fig. 14), extending from the 

 base of the tail to the base of the caudal papillae. 



There are two pairs of precloacal genital papillae (figs. 13 and 14), 

 one pair of adcloacal papillae, and one pair of caudal papillae located 

 at the posterior end of the alae. The precloacal pairs seem to arise from 

 the same base on each side, and thus are interpreted as double papillae. 

 Each has a separate nei-ve ending and the nerve fibers could be seen to 

 branch from a common stem to each of the papillae. These papillae are 

 considered sessile. Adjacent to these papillae are two fingerlike projec- 

 tions, the cloacal lips. The adcloacal papillae are situated on long slender 

 stalks which arise from the body anterior to the cloacal aperture. These 

 two papillae are well developed and are between the cloacal lips and 

 accessory piece. The pedunculated caudal papillae are situated at the 

 anterior of the distal quarter of the tail. Thus there are four pairs of 

 genital papillae, two of which are sessile and two are pedunculated. 



