The Hlrudinca of lUiuois. 541 



two rows of papillae. The anus cuts the second, which bears, 

 but very few papilhe. XXVII is postanal and biannulate. 



Reproductive Organs. — The numerous small testes are found 

 in somites XVIII to XXIII, but their number was not deter- 

 mined. The vasa deferentia, sperm-sacs, and ducti ejacula- 

 torii are sufficiently indicated in the figure (PI. XLVIL, 

 Fig. 37). The latter end abruptly, without any preatrial 

 loop whatever, at the prostate horns, into the ends of which 

 they empty. 



The atrium is a very characteristic one and differs from 

 that of any other species of iVmerican nephelid which I have- 

 examined. It may be remarked in passing that the eft'erent 

 male apparatus of this species and Diiia fervida have many 

 characters in common which distinguish them from iKmexl- 

 cdua Duges, -which Blanchard regards as being co-specific 

 with the type of the genus. The median chamber {at) is a 

 thick-walled sac of relatively large size. It stands up promi- 

 nently from the body floor, raising the nerve cord with it and 

 barely marked by a median groove. Its transverse diameter 

 is much greater than the antero-posterior and about equal to 

 its height, but in immature specimens the organ is spherical. 



The prostate cornua {p) are small, — when straightened, 

 less than the shortest diameter of the median chamber, — and 

 their attachments are far apart on the dorsal surface of this 

 chamber, with which they remain in close contact as they 

 curve strongly ventrad on each side. At their lowest point 

 at the sides they become continuous with the ducti ejacu- 

 latorii as above described. 



The ovaries {ov) present no peculiar features, and their form 

 and relations are sufficiently indicated in the figure. 



Color. — Not one of many examples of both young and old 

 shows any pigment. This would indicate that during life 

 they are red, the color of the blood showing through the 

 integuments. 



Small tul>ifjcid worms have been found in the stomachs of 

 those examined. 



