NO. 3 HARTMAN: POLYCHAETOUS ANNELIDS 215 



on the other hand, these species were first grouped into those with, and 

 those without, falcigerous notopodial setae, a more definite criterion for 

 separation might be attained. This would, however, necessitate a redistri- 

 bution of species within a genus, and a reexamination of many type speci- 

 mens in which this character has not been made known. 



Numerous species of Nereidae have been described from the tropical 

 and subtropical eastern Pacific. Some of these have not been redescribed 

 since first named, and in some instances identity is hardly possible. Such 

 are the following: Nereis castelnaui, N. rupta, and N. pacifica, described 

 by Quatrefages (1865, pp. 522-524) from Peru. The name of the last 

 was later changed to A^". peruviana Ehlers ( 1868, p. 460, footnote) with- 

 out a redescription. Nereis chlorodes, N. delicatula, and N. gayi by 

 Blanchard (1849, pp. 22-23), as also Mastigonereis cuprea and Nereis 

 maculata Schmarda (1861, pp. 112, 102), were described from Chile. 

 Kinberg (1866, p. 173) described Heteronereis grubei from Valparaiso 

 and Nereis tredecimdentata from the Galapagos Islands (1866, p. 169). 

 Heteronereis pannosa from Callao, Peru, and Nereis rigida from Punta- 

 renas were named by Grube (1856, pp. 167-172). If the types of these 

 species were to be reexamined, they might be found to be conspecific witR 

 subsequently described species. 



Key to Genera 



1. Peristomium produced so as to project forward, collarlike, 

 under the prostomium; commensal with pagurids .... 

 CHEILONEREIS,p.219 



1. Peristomium not so produced 2 



2. Proboscis without paragnaths; notopodia without falcigerous 

 setae LEPTONEREIS, p. 216 



2. Proboscis with few to many paragnaths; notopodia with or with- 

 out falcigerous setae 3 



3. Paragnaths present only on maxillary ring; notopodia with or 

 without falcigerous setae . . . CERATONEREIS, p. 217 



3. Paragnaths present on both oral and maxillary rings ; notopodia 

 with or without falcigerous setae 4 



4. Paragnaths on both rings are conical 5 



4. Paragnaths are conical except those on area VI (or also on area 

 V), which are transverse; notopodia without falcigerous setae 

 PERINEREIS, p. 229 



4. Paragnaths on the maxillary ring are pectinate 6 



