Proceedings of 

 the United States 

 National Museum 



SMITHSONIAN INSTITUTION • WASHINGTON, D.C. 



Volume 121 1967 Number 3575 



SOME BATHYAL POLYNOIDS 



FROM CENTRAL AND NORTHEASTERN PACIFIC 



(POLYCHAETA: POLYNOIDAE) 



By Marian H. Pettibone 



Associate Curator, Division of Worms 



Polychaetes obtained from bathyal and abyssal regions are delicate 

 and, thus, easily mutilated. Among the polynoids, the dorsal scales 

 or elytra are usually missing; the styles of the antennae and the 

 tentacular, dorsal, ventral, and anal cirri are often partly or completely 

 missing; the setae and even the parapodia may be broken off; in 

 addition, the body may be fragmented. 



This study of some deepwater poljaioids was prompted by the dis- 

 covery of a single, somewhat mutilated specimen of polynoid collected 

 in 900 fathoms off the mouth of the Columbia River, Oregon. It is 

 herein described as a new species belonging to a new genus, Bathyad- 

 metella. As the name mdicates, it shows certain affinities to Admetella 

 Mcintosh. 



The generic standing of Admetella, based on Polynoe (Admetella) 

 longipedata Mcintosh (1885), was first indicated by Darboux (1900). 

 Darboux gave a diagnosis for the genus based on the incomplete de- 

 scription by Mcintosh. The description of A. longipedata has been 

 supplemented subsequently by other polychaete workers, particularly 

 by Augener (1906), Ehlers (1908), and Ditlevsen (1917). Some speci- 



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