286 Illitiois State Laboratory of Natural History. 



species of the genus thus far described, while it agrees with 

 -all but D. vernicosa Ude, (15) in the presence of prostate 

 glands opening upon XVIII and XX. The prostate- 

 gland pores are connected on each side by a longitudinal 

 groove. The male pores are upon the anterior part of 

 XIX. The clitellum is nearly as thick upon the ventral 

 part of the somites as upon the dorsal, except upon 

 XVII and XVIII. A pair of genital papill£e is situated 

 upon the posterior part of XVII or the anterior part 

 of XVIII, and a second pair occurs upon XX or XXI, 

 the position of both ])airs being variable. 



The testes and ovaries and the funnels of the sperm 

 •ducts are present in the usual number and situation, 

 and the sperm sacs agree in number and arrangement 

 with those of the other species of the genus. The dorsal 

 vessel is single. The nephridia of the first pair are very 

 small and open upon II. The position of the first dor- 

 sal pore is not uniform, being in some specimens in the 

 anterior part of IX and in others in the anterior part 

 of X. In the other species of the genus I have found it 

 in the anterior part of XI, where it is stated by Ude to 

 occur in D. singularis. The penial setae of the specimens 

 studied by me are long and slender, but have a slight 

 ■double curve instead of the form figured by Ude (14, 

 Fig. 18). The veutral setae are absent upon XIX, as 

 the in some of the other species. The anterior end of 

 worm is dark-colored upon the dorsal surface, as in D. 

 eiseni Mich, and in D. rlparia. 



Diplocardia riparia Smith. 



Since writing a previous paper (12) in which I described 

 the above species and compared it in some particulars 

 with Diplocardia {Geod/rilm) eiseni Michaelsen (8, p. 184), 

 I have received, through the kindness of a friend in 

 Florida, forty-one living specimens of D. eiseni which 

 •were collected last June from the banks of Lake Eola 

 in that state. A comparative study of these worms and 



