406 J. STAFPORD, 



are delicate tubes running direct to tlie penis sack the broad posterior 

 end of which lies above the right side of the ventral siicker and con- 

 tains a vesicula seminalis. The anterior end curves round to the left 

 and opens between the sucker and the fork of the intestine. 



The ovary is also a globular body, smaller than the testes, and 

 to the left of the ventral sucker. Near the ovary the oviduct is joined 

 by a receptaculum seminis and from the junction diverges a Laurer's 

 canal which bends upwards to open in the raid-dorsal line, above the 

 ventral sucker. Ootype, shell gland and receptaculum seminis uterinum 

 follow; the latter passes into the uterus, which forms many foldings, 

 right and left, between the branches of the intestine. The space 

 beyond the blind ends of the caeca is also crowded füll to the body 

 walls. From here the uterus returns in a similar fashion towards 

 the middle of the body and opens by a vagina, with the penis, into 

 the unpaired genital cloaca. 



Vitellaria or yolk glands lie between the prongs of the intestine 

 and the lateral body walls and are composed of a considerable number 

 of follicles, whose narrowed necks open into longitudinal vitelline 

 ducts. These glands occupy the lateral regions of the middle half of 

 the body. I have not foUowed the ducts in detail but I suppose 

 there are two transverse vitelline ducts, that conduct the yolk cells 

 from the before mentioned longitudinal ones to a vitelline reservoir 

 and that this opens into the oviduct in the region of the shell gland. 



It will be Seen, as I have already intimated, that there are certain 

 resemblances to D, endolohum. But there are also many difl'erences, 

 some of which I shall enumerate. 



Small ventral sucker. 



Pharyngeal glands. 



Ovary left of sucker instead of right (I describe the position of 

 the Organs as they appear in the Compound microscope). 



Testes spherical. Their lateral position, and in the middle of the 

 body. Also left one most posterior. 



Vitellaria in middle region. 



Long Uterus, filling posterior part of body. 



Long expulsion canal. 



5. Ulstonium chelydrae n. sp. 



The Distome thus conveniently designated occurs in the intestine 

 of the Snapping Turtle {Chehjdra serpentina). — It measures about 

 6 mm in Icngth, and scctions are 0.735 mm broad and 0.420 mm 



