532 Illinois State Laboratory of Natural History. 



specimens of the terrestrial variety. On living aquatic ex- 

 amples from Ohio the dorsal black stripe may be conspicu- 

 ous, but is. more frequently faint and obscure, broken into 

 small spots, or totally wanting. 



Habits. — The habits of this species have been briefly 

 described by Say ('24) and Forbes ('90). 



HERPOBDEKLIDJE. 

 "Erpobdella Blainville. 

 Erpobdella punctata (Leidy). 



Nephelis punctata Leidy ('70). 

 Nephelis lateralis Bristol (in part) ('98). 



It has been found impossible to certainly identify this with 

 any of Yerrill's species. There is little doubt that Nephelis 

 lateralis Yerrill and Nephelis quadristriata Verrill are founded 

 on two distinct species which are common in New Eng- 

 land and both of which are quite distinct from Leidy's 

 species ; but N. quadristriata, Verrill (not Grube) may be in 

 part synonymous with E. punctata. 



Diagnosis. — Complete somites quinqueannulate, b 6 some- 

 times slightly larger than the other annuli but not typically 

 divided in the middle by a cross-furrow ; pigmented eyes three 

 pairs, the first situated on II, the second and third on IV ; 

 genital orifices, male at XII 6 2/a2, female at XII b 5/b 6; 

 atrium deeply cleft, the prostate cornua prominent, and the 

 anterior loops of the vasa deferentia reaching to ganglion XL 



General Description. — Bristol ('98) has given an excellent 

 description of the external characters, the annulation, and the 

 neural metamerism of this species, most of which need not be 

 repeated, especially as the external features distinguishing 

 species of this family are mostly slight and obscure. The 

 number and arrangement of the external annuli may be 



*Blainville's original spelling is here followed. Blanchard has changed this to 

 Herpobdella, and separated the family from the Hirudinidce. 



