ANNELIDA POLYCHAETA. 161 



NOTE XXXIV. 



CONTRIBUTIONS TOWARDS THE KNOWLEDGE 

 OF THE ANNELIDA POLYCHAETA. 



Dr. R. HORST. 



Ill !). 



On species of Nereis , belonging to the sub-genus Perinereis. 

 (Plate 7 and 8). 

 The sub-genus Perinereis, according to Grube's views, 

 contains all Nereis -species , characterized by having the 

 lateral dorsal paragnathi of the basal ring of the proboscis 

 (group VI) all or some of them transverse , ridge-shaped , 

 the remaining paragnathi being conical, or pin-shaped 

 (»pectiniformes" Kinberg), or compressed; the feet all of the 

 same structure, or those of the posterior region of the body 

 more enlarged. This division mainly corresponds to Kinberg's 

 family Aretidea, and not to his genus Perinereis , con- 

 taining the species , which have no pectiniform teeth and 

 but little modified posterior feet. However it seems prefer- 

 able to me to maintain Kinberg's name , as I do not like 

 to increase the systematical literature with a new one, and 

 because the greatest number of species of the family Are- 

 tidea are united in the genus Perinereis , the four other 

 genera {Arete , Pseudonereis , Paranereis and Naumachius) 

 containing only a small part of them. To use the name 

 Lipephile, afterwards proposed by Malmgren for N. cultri- 

 fera , instead of Perinereis , as done by Claparède a. o. , 

 seems not justified to me, because the name Perinereis has 

 the priority , and moreover the name Lipephile is applied 



1) For Part I see Vol. VIII, p. 157, and for Part II Vol. XI, p. 37. 

 Notes from the Leyden Museum , Vol. XI. 



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