174 PROCEEDINGS OF UNITED STATES NATIONAL MUSEUM. 



Lumbriuereis hebes VerriU. 



Lumbriconereis oMusa Verrill, Proc. Amer. Assoc, for 1873, p. 383, 1874. 



The name obtusa having been preoccupied in this genus, the above 

 name is proposed as a substitute. 



Goniada gracilis Verrill. 



i:one gracilis Verrill, Eeport on Invert, of Vineyard Sound, etc., p. 302, 

 1873, (vol. i, Eep. of U. S. Com. of Fish and Fisheries, p. 596). 



This species has upon its proboscis the two rows of V-shaped denti- 

 tles (in chevron) and also the jaws as in Goniada, to which genus it should, 

 thereforCj be referred. 



Polydora gracilis, sp. nov. 



Small, 3""" to 4™™ long, very slender. Antennns stout, blunt, very 

 long, six times as long as breadth of body, or even more, transversely 

 wrinkled. 



Head with a long, narrow, oblong, central i:>ortion, acute behind, 

 notched or bilobed in front, with the two anterior corners rounded and 

 a little prominent ; side lobes of the head not broad, gradually narrowed 

 toward the front ; eyes four, the front pair conspicuous, decidedly larger 

 and but little wider apart than the others, which are small and but lit- 

 tle farther back. 



The four anterior segments have small, rounded, dorsal papillte, with 

 capillary setae ; on the fifth there are fascicles of about six large special 

 setse, of which the posterior are shorter. On the sixth and following 

 segments, there are, with the capillary sette, three or four uncini in the 

 dorsal fascicles. Branchice elongated, commencing on the seventh seg- 

 ment, absent on the twelve posterior segments. Caudal appendage 

 sucker-like, with a smooth margin, surrounded by a marginal circle of 

 dark specks. Color pale salmon or light flesh-color j antennae and head 

 with dark specks. 



Off Block Island, 1873, gregarious in galleries in Pecten tenuicostatus, 

 and ha\iug slender sand-tubes projecting from the orifices in the shell. 



Polydora concharum, sp. nov. 



A very long, slender species, having more than 200 segments, and 

 often becoming four or five inches long. 



Head, or cephalic lobe, narrow in front, projecting considerably be- 

 yond the wide lateral lobes (formed by the buccal segment), and deeply 

 divided at the end into two lanceolate, acute, divergent lobes. Eyes 

 four, small, but conspicuous, black, the anterior ones much wider apart 

 than the posterior, and but little farther forward. In some specimens, 

 the eyes are absent. Antennte very long and slender, fifteen to twenty 

 times as long as the diameter of the body, or more, whitish or pale flesh- 

 color, with a central red vessel, and usually with a fine dark line on each 

 side. Buccal segment large and swollen below, witli longitudinal sulci 

 extending back from tlie mouth. On the four anterior segments, the 



