V 



482 PROCEEDINGS OF THE ACADEMY OF [Sept., 



Posteriorly the pharyngeal cavity communicates with the spacious 

 chamber of the main gut which extends backward close to the 

 posterior end of the animal, giving rise to seven or eight pairs of 

 intestinal branches during its course. These last-named structures 

 are at first of even caliber, but soon become swollen and greatly 

 constricted, giving the impression of a dichotomously arranged 

 system of large spherical vesicles. 



The brain is situated immediately in front of the pharynx, but 

 otherwise the details of the nervous system have not been determined 

 clearly. 



The testes are ventral and in some cases are united by anasto- 

 mosing sperm capillaries (PI. XIV, fig. 18) that, on the other hand, 

 unite with the vasa deferentia. The latter originate at the level 

 of the sucker, and, pursuing a tortuous course as they proceed 

 anteriorly, they finally swing inward at a point not far behind the 

 pharyngeal pocket. Here they unite (PI. XVII, fig. 34) and as single 

 tube proceed anteriorly into the base of the penis. At the same 

 point where the penis receives this median duct it also communicates 

 with the outlet of the ample and elliptical granular gland. There 

 is no seminal vesicle. The penis is moderately thin walled and inflated 

 and is guarded by a closely enveloping sheath which in turn lies at 

 the base of an antrum masculinum of average proportions. 



The ovaries are dorsal and in some specimens are clearly united 

 by a system of capillaries that unite with the uteri close to the 

 outlet of the so-called uterus glands. In a general way the uteri 

 (PI. XIV, fig. 18) may be said to arise midway between the sucker 

 and the posterior end of the gut, and from this point to extend for- 

 ward, anastomosing somewhat, to turn sharply inward opposite a 

 point midway between the sucker and the anterior gut-end. Here 

 they fuse (PI. XVII, fig. 34) into a median duct, the vagina, that 

 leads to a small antrum femininum and to the exterior immediately 

 behind the point of fusion of the vasa deferentia. In the location 

 where each uterus commences to swing in toward the mid line, it is 

 joined by a short duct leading from a well-developed uterus gland 

 of varying size according to the proximity of the breeding season. 

 They may be almost spherical or contracted into a thin crescent or, 

 as appears to be a more usual state, elliptical. The duct leading 

 from it arises from the inner surface of the gland. 



EURYLEPTODES gen. nov. 



Pharynx relatively small; main gut slender with 7 to 8 anastomosing 



