402 PROCEEDINGS OF UNITED STATES NATIONAL MUSEUM. 



ations of A. glaciaUs. The shortest and most rounded forms that we have 

 taken were dredged south of IMartha's Vineyard and south of Newport, 

 in 85 to 225 fathoms, this season. 



Limopsis cristata (?) Jeffreys. 



Ann. and Mag. Nat. Hist., 1876, p. 434; Proc. Zool. Soc. London, 1879, p. 585, 

 pi. 4(3, fig. 8. 



A few dead specimens, referred doubtfully to this species, occurred at 

 stations 865 to 807 and at 870 and 871, in 65 to 155 fathoms. 



Limopsis minuta (Pliilippi). 



G. O. Sars, Moll. Eeg. Arct. Norv., p. 44, pi. 3, figs. 5 a-c. 



Limopsis ftoreaZiS Jeffreys, Brit. Conch., ii, p. 164; v, p. 174, pi. 100, fig. 3. 



This shell was taken in abundance, living, at stations 893, 894 and 895, 

 in 238 to 372 fathoms ; in smaller numbers at 891 and 892, in 487 to 500 

 fathoms ; and sparingly at several other localities in 115 to 252 fathoms. 



Modiola polita Verrill & Smith. 



Amer. Journ. Sci., xx, p. 400, for Nov., 1880 (puhlished Oct. 25). 



Two living specimens were taken at station 895, in 238 fiithoms. 



Avicula hirundo (?) L., var. nitida, nob. 



The shell is very inequivalve, the right shell being smaller and flatter, 

 and much bent inward near its ventral edge. The form is very oblique, 

 with the anterior ear small and short, in the left valve, and separated from 

 the body of the shell by a slight incurvature of the edge, from which a 

 depression runs to the beak ; right valve with a shallow byssal notch. 

 Posterior ala short, triangular, with a rounded incurvature of the pos- 

 terior edge of the shell, separating it from the body of the shell, which 

 is produced and rounded at the end. Surface nearly smooth, glossy, 

 and somewhat iridescent, with regular but inconspicuous lines of growth, 

 which on the anterior ears rise up into thin, wavy laraelhe. 



Color translucent, pale yellowish, usually with a brown streak radi- 

 ating from the beak to the outer edge. 



Length, beak to outer edge, 13"""; length of hinge-line, 11"""; beak to 

 end of posterior ala, 8'""'. 



This shell was found in considerable numbers adhering to hydroids, 

 in Go to 192 fathoms, south of M;irtha's Vineyard (stations 865 to 867, 

 and 809 to 873). In form it resembles the young Avicula Mriincio of 

 Florida and the West Indies. It is, however, much smoother and more 

 lustrous than any specimens of that species which I have hitherto seen, 

 and may well prove to be a distinct species, for which I would, in that 

 case, propose the name nitida. 



Limcea subovata (Jeffreys). 



Lima suhovata Jeffreys, Annals and Mag. Nat. Hist., Nov., 1876, p. 427. 

 Shell small, white, ovate, nearly equilateral, with the valves convex, 

 much swollen in the middle; beaks prominent, incurved; hinge-line 

 straight, shorter than the shell j ligament-pit narrow, elongated, lunate. 



