A. E. Terrill- — Catalog * of 3L> 'in*. AloUmoa. 
565 
Variety. TOtundata Jeffreys. 
Poromya rotundato. Jeffreys. Annals and Mag. Nat. Hist., Dec.. 1876. p. 494 ( Val- 
orous Expedition Mollusca). 
Verrill, Amer. Journ. Sci.. xx. p. 392. Nor.. 1S80; Proc. U. S. Nat. Mus., iii. p. 
396, 1880. 
South of Martha’s Vineyard, stations 865 and 871, 65 to 115 
fathoms, living. North Atlantic, 1,450 fathoms (Jeffreys). 
Having recently had opportunities to examine a larger series of 
specimens of this species, I am convinced that the form, rotundato. 
Jeffreys, formerly recognized by me cannot be considered as specifi- 
cally distinct. Intermediate forms are of frequent occurrence. 
As a variety, it differs from the ordinary form only in being some- 
what more rounded in form, and in having the surface more closely 
and uniformly covered with granules. In the last character, this 
species varies greatly. 
Pecchiolia abyssicola G. 0. Sars. 
Pecchiolia abyssicola G. 0. Sars, .Remarkable Forms of Anim. Life, i, p. 25. pL 3, 
figs. 21—43. 1872 ; MolL Reg. Arex. Norv., p. 108. pi. 20, figs. 5 a-d, 1878. 
LyonsieUa abyssicola JL Sars. 1358: Friele. fatal Norv. N.-meer Exp. Spitzbergen. 
Moll., p. 268, 1879. 
Verrill Proc. E. S. Nat. Mus., iii, p. 396, 1880. 
This little fragile shell may be distinguished by its quadrangular 
form, with the beaks incurved, and the surface covered with low 
radiating ribs, to which fine sand often adheres. The shell is very 
thin and somewhat pearly. The hinge-margin is thin, and the teeth 
obsolete. 
Several good living specimens of this interesting addition to the 
American fauna were dredged by our party, in 1880, south of 
Martha’s Vineyard and Newport, in 192 to 500 fathoms, fine, com- 
pact sand and mud, at stations 869, 880, 891, 892, 894. In 1881, it 
occurred at stations 947, 997, in 312 and 335 fathoms. 
On the Europeau coast from Spitzbergen (656 fathoms, — Friele), 
to Denmark. Davis Straits, — Valorous Exp. West of Ireland. 90 
to 420 fathoms; oft' the English Channel, 557 fathoms; off the 
coast of Spain, 994 to 1095 fathoms, Porcupine Exp. (t. Jeffreys.) 
Pecchiolia gemma Verrill. 
LyonsieUa gemma Verrill, Proc. U. S. Nat Mu«.. iii p. 396. 1880. 
Shell small, white, iridescent, broad-oval, widest and broadlv 
rounded anteriorly, expanded and broadly rounded ventral ly, pos* 
