Two Neio OUgochceta from Illinois. 



141 



The new species, then, possesses all the characters of 

 D. conimunis which are regarded by Garman as generic 

 except two; viz., three pairs of spermathecse and a 

 double dorsal vessel. Not regarding these characters as 

 of generic importance, foi" the reasons given above, I in- 

 clude the new species in the genus Diplocardia. 



The more obvious external charactei's b3' which this 

 species may be distinguished from D. communis are 

 smaller size, darker color, — especially of the anterior 

 portion, — the presence of but two pairs of spermathecal 

 pores, and the single dorsal vessel, which in the living- 

 animal is plainh^ visible through the body wall. 



For convenience of comparison the following table has 

 been prepared : 



Diplocardia communis. 



Diplocardia ripnria. 



Setae 



Prostomium. 



Male pore 



Testes and funnels — 

 Speim-oacs 



Prostates. 



Copulatory fossae or 

 longitudinal grooves. 



Ovaries 



Female pore- 

 Gizzards 



Typhlosole -Uight dorsal fold 



Four couples. 



A.11 ventral, 

 into 



Partial'y dovetailed 

 peristomium. 



XIX. 



X and XI. 



Sacculated in IX and XII. 

 X and XI filled with sper- 

 matozoa without special 

 sac. 



Two pairs, with external 

 openings in XVIII and XX. 



One pair, extending from 

 middl ■ of XVIII to middle 

 of XX, with eopulatory 

 f^etffi and prostate pore at 

 the extiemitios of each 

 groove. 



One pair in XIII. 



XIV. 



Two; in V and VI. 



Subneural vessel. 

 Nophridia 



Nephridiopore in line 

 with 



Clitellum. 



Absent. 

 Meganephric. 

 F 'urth seta. 



XIII-XVIII. Incomplete. 



Four couples. All ventral. 



Partially dovetailed into 

 P'^ristomium. 



Anterior part of XIX. 



X and XI. 



Sacculated in IX and XII. 

 X and XI filled with sper- 

 matozoa without special 

 sac. 



Two pairs, with external 

 openings in XVIII and XX. 



One pair, extending from 

 middle of XVIiI to middle 

 of XX, with eopulatory 

 setae and prostate pore at 

 ihe extremities o*' each 

 gioove. 



One pair in XIII. 



XIV. 



Two; in V and VI. 



Slight dorsal fold. 



Absent. 



Meganephrio. 



Fourth seta. 



XIII-XVIII. Incomplete, 

 or b'Jl slightly developed 

 upon narrow median ven- 

 tral area. 



