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is placed a wliite, calcareous, calcarate dart. At the 

 junction of the vagina, common to the neck of the ovi- 

 duct, duct of the generative bladder, and the dart sac, 

 with the penis, there are two short retractor muscles 

 inserted. The cloaca is narrow and cylindrical, and has 

 surrounding two-thirds of its middle, a thick, glandular 

 organ. Interiorly, the penis, cloaca, etc. have a longi- 

 tudinally rugous surface. 



Vaginulus. a remarkable peculiarity of this genus 

 is the removal of the male and female portions of the sex- 

 ual apparatus from each other. The former, except the 

 testicle and prostate gland, occupies the usual position, 

 but opens externally between the mouth and olfactory 

 orifice ; the latter is placed in the middle inferior part of 

 the \asceral cavity, and opens exteriorly on the right 

 side, inferiorly just posterior to the middle of the body. 



The testicle is situated between the posterior part 

 of the stomach and the liver, on the right side. It is 

 not lobulated, but has the same aciniform arrangement 

 as m the preceding genera. The epididymis is mode- 

 rately tortuous, and becomes the vas deferens at the 

 junction of the ovary with the oviduct. The vas deferens 

 takes a remarkable course to get to the penis. It is, at 

 first, attached for a short distance to the commencement 

 of the oviduct, which it leaves, and then winds around its 

 lower extremity, where it is joined by a comparatively 

 very small prostatic gland. It continues its attachment 

 to the lower part of the oviduct to the junction of the 



