PROCEEDINGS OF UNITED STATES NATIONAL MUSEUM. 397 



front of them, so as to rise nearly to a level with the ninbos ; internally, 

 oi)posite the tips of the beaks, there is a smooth swelling within the 

 margin. Hinge margin thin, toothless, but with an internal sear behind 

 the beaks, where the ligament and ossicle were attached (the ligament 

 is gone). Palial sinus very small, angular. Shell less thin than in the 

 preceding species. Sculpture numerous, very delicate, slightly raised 

 lines, which radiate from the beaks over the whole surface ; they are 

 separated by much wider interspaces, which are smooth and iridescent, 

 and not at all excavated. Length, 4.5'""^; height (beak to ventral mar- 

 gin), 4""". 



One perfect specimen, station 892, 487 fathoms, associated with L. 

 ahyssicola. 



From the latter it differs widely in shape, having nothing of the rect- 

 angular form so characteristic of that species ; the latter is also much 

 less expanded anteriorly and much more so posteriorly, being far more 

 inequilateral and more elongated. 



Kennerlia glacialis (Leach) Carpenter. 



Pandora glacialis Leach, Eosse's Voyage, appendix, p. 174. — Leche, Kongl. 



Vetensk.-Akad. Handl., Baud 16, p. 11, pi: 1, figs. 1 a, h, 1878 (author's 



copy). 

 Living specimens of this arctic shell were dredged at station 873, in 

 100 fathoms. It had previously been recorded from the Gulf of Saint 

 Lawrence by Whiteaves, but was not known to occur on the New 

 England coast. It diliers widely from the common Clidiopltora trilineata 

 Cin\{ = Pandora trilineata Say), in the absence of the internal radiating 

 ridges, in its more inequilateral and irregular form, and in the greater 

 convexity of the upper valve. The lower valve is very flat, or even con- 

 cave, and is marked externally with several distinct radiating lines. 



Neaera glacialis. 



G. O. Sars, op. cit.,p. 88, pi. 6, figs. 8 «-c.— Verrill, Trans. Coun. Acad., v., pi. 

 44, fig. 10 I). 



A form of Xemra^ agreeing perfectly with this, is common on muddy 

 bottoms, in 50 to 192 fathoms, oft' the coasts of New England and Nova 

 Scotia. We have dredged it off Cape Cod, off Cape Ann, otf Casco Bay, 

 in the Bay of Fundy, and in numerous localities in the Gulf of Maine 

 and otf Nova Scotia, since 1872; and recently, south of Newport and 

 Martha's Vineyard, in 65 to 500 fathoms. The larger specimens exceed 

 an inch in length. 



Among our numerous examples there is, however, considerable varia- 

 tion, both in the form of the shell and in the size and shape of the car- 

 tilage-pit and lateral teeth. Moreover, the variations in the hinge are 

 not correlated with the diflerences in the breadth and length of the 

 rostrum. Therefore, it seems to me probable that this shell should be 

 considered merely a variation of N. arctica. The latter, in its typical 

 form, occurs in the same localities and in about the same numbers, and 



