t 
382 PROCEEDINGS OF UNITED STATES NATIONAL MUSEUM. 
It is a small, very smooth, white shell, in form closely resembling 
young specimens of Cylichna alba, for which it may easily be mistaken. 
It lacks the fine spiral lines usually seen on the latter, and is rather 
more narrowed posteriorly. The apex of the spire is occupied by a shal- 
low depression, and there is no umbilicus. 
Diaphana gemma Verrill. 
Amer. Journ. Sci., xx, p. 399, Nov., 1880. 
Shell oblong, suboval, widest a little in front of the middle, truncate 
posteriorly and obliquely rounded anteriorly, with a distinct umbilicus, 
and also with a narrow, deep pit at the apex. Texture of shell rather 
solid, somewhat thickened. Outer lip rising somewhat above the spire, 
forming a rounded posterior angle; throughout most of its length only 
slightly convex, often nearly straight; anteriorly, a little expanded and 
produced, well rounded, thickened. Inner lip more thickened, with 
the edge a little ani but leaving a small and regular umbilicus. 
Aperture narrow posteriorly, ovate anteriorly. Surface smooth and 
glossy, without any sculpture over the middle region, but with several 
well-defined, not crowded, but fine spiral grooves at each end, visible 
with a lens. Color grayish white. Length, 4.2"; breadth, 2.5". 
Stations 871 and 873, 100 to 115 fathoms, fine gai south of Martha’s 
Vineyard and Newpor t, kh. I. 
I have had no opportunity to examine the animal of this species, and 
refer it to Diaphana, provisionally, because of its resemblance to D. wnbil- 
icata. It may prove to be a Cylichna. It has some resemblance to C. 
occulta Mighels (= C. propinqua Sars). The latter is, however, destitute 
both of the pit at the summit of the spire and of the umbilicus, and its 
surface is everywhere covered with distinct spiral lines. Our shell is 
shorter and stouter than D. wmbilicata. 
Diaphana conulus (Desh. ). 
Utriculus conulus G. O. Sars, op. cit., p. 287, pl. 17, figs. 17 a-e. 
A perfect living specimen of this very distinct species was taken at 
station 870, in 155 fathoms. It has not been recorded hitherto from the 
American coast. 
Amphisphyra globosa Lovén, 1846. 
Diaphana globosa G. O. Sars, op. cit., p. 290, pl. 18, figs. 3¢, 4; pl. xi, fig. 12 
(dentition ). 
Specimens agreeing in all respects with Sars’s figures, referred to 
above, were dredged at stations 870, 871, and 894, in tee to 565 fathoms, 
south of Martha’s Vineyard and N ewport. 
Amphisphyra pellucida (Brown) Lovén, 1846. 
Diaphana pellucida Brown, Ill. Recent Conch., pl. 19, figs. 10, 11, 1827. 
Bulla hyalina Turton, Mag. Nat. Hist., vii, p. 353, 1834 (non Gmelin). 
. Bulla debilis Gould, Invert. Mass., ed. i, p. 164, fig. 95, 1841. 
Utriculus hyalinus Jetireys, Brit. Conch., iv, p. 427; v, pl. 94, fig. 7. 
Diaphana hyalina G. O. Sars, op. cit., p. 289, pl. 18, figs. 1 a, b; pl. xi, fig. 10 
(dentition). 
Diaphana debilis Gould, Invert. Mass., ed. ii, p. 216, fig. 507. 
This species occurred at stations 876 and 894, in 120 and 365 fathoms. 
