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Leda unca Gould.

Proc. Bost. Soc. Nat. Hist., viii, p. 282, 1832.-Otia Conch., p. 239 (=? Leda acuta Conrad, described as fossil).

Many of our specimens are much larger than the shells described by Gould and Conrad. Our larger specimens are 13mm long, 8mm broad.

This shell is rather strong and thick, oval, swollen, rounded anteriorly, but posteriorly narrowed to an acute, short, angular beak, at the base of which there is a slight incurvature of the ventral edge. The nearly straight posterior dorsal edge slopes regularly to the beak, and is somewhat compressed or keeled. The whole surface is covered with numerous prominent, regular, rounded, concentric ribs, separated by deep grooves of about the same width. On the posterior dorsal area these ribs are smaller, and are often nearly obsolete close to the edge.

Taken in considerable numbers, alive and dead, at many of the stations, both south of Martha's Vineyard and south of Newport, R. I., in 85 to 155 fathoms, especially at stations 871, 873, 874, and 876.

This species appears to be allied to L. Messanensis Cant. (= L. acuminata Jeff.), from deep water in the Mediterranean.

Leda pernula (Müller).

G. O. Sars, op. cit., p. 35, pl. 5, fig. 1 a-d.

A specimen that appears to be a typical example of this speceies was dredged by us in 1877, off Halifax, in 59 fathoms. It has a smooth, lustrous, yellowish green epidermis. The concentric grooves are irregular and mostly obsolete, except anteriorly, where they are fine and close. The form is similar to that of L. tenuisulcata. Length, 23mm; height, 10.

Yoldia frigidia Torell.

Spitz. Moll., p. 148, pl. 1, fig. 3, 1859.—G. O. Sars, Moll. Reg. Arct. Norv., p. 39, pl. 4, figs. 11 a, b.

This species occurred at station 894. It had not previously been obtained off the New England coast, but had been dredged in the Gulf of Saint Lawrence, by Whiteaves, in 200 fathoms.

Arca glacialis Gray.

G. O. Sars, op. cit., p. 43, pl. 4, figs. 1 a-c.-Verrill, Trans. Conn. Acad., v, pl. 44, fig. 5.

This species has been dredged in numerous localities by the various dredging parties of the United States Fish Commission, since 1872, in the Bay of Fundy, Gulf of Maine, off Cape Cod, on George's and Le Have Banks, and off Halifax, Nova Scotia, at various depths from 90 to 430 fathoms; about 70 to 75 miles south of Martha's Vineyard, in 115 to 192 fathoms, and south of Newport, in 85 to 500 fathoms. It attaches itself to pebbles or gravel-stones by a small but strong ventral byssus.

The shorter and more rounded form, known as Arca pectunculoides Scacchi, also occurs on our coast, as well as the deformed variety called var. septentrionalis by G. O. Sars. These appear to me to be mere vari Proc. Nat. Mus. 80-26 Jan. 10, 1881.

ations of A. glacialis. The shortest and most rounded forms that we have taken were dredged south of Martha'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, pl. 46, fig. 8.

A few dead specimens, referred doubtfully to this species, occurred at stations 865 to 867 and at 870 and 871, in 65 to 155 fathoms.

Limopsis minuta (Philippi).

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

Limopsis borealis Jeffreys, Brit. Conch., ii, p. 164; v, p. 174, pl. 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 (published Oct. 25).
Two living specimens were taken at station 895, in 238 fathoms.

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 posterior 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 lamellæ.

Color translucent, pale yellowish, usually with a brown streak radiating from the beak to the outer edge.

Length, beak to outer edge, 13; length of hinge-line, 11; beak to end of posterior ala, 8mm.

This shell was found in considerable numbers adhering to hydroids, in 65 to 192 fathoms, south of Martha's Vineyard (stations 865 to 867, and 869 to 873). In form it resembles the young Aricula hirundo 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.

Limæa subovata (Jeffreys).

Lima subovata 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; ligament-pit narrow, elongated, lunate.

Sculpture very numerous (70 to 80 or more) radiating ribs, fine laterally, increasing in strength on each side to the middle, where there are two or three ribs considerably larger than the rest, with wider intervals; the ribs and intervals are crossed by fine, close, raised lines of growth. Interior with radiating lines corresponding to the external ones. Length, 4mm; height (beak to ventral edge), 7mm; thickness, 4. Station 880, 255 fathoms, scarce; 891 to 894, 365 to 500 fathoms, common. Limaa gibba (= Lima gibba Jeffreys, op. cit., p. 428) also differs but little from our specimens.

Pecten fenestratus Forbes (?).

Report on Mollusca, &c., of Egean Sea, p. 146, in Proc. British Assoc. for 1843.
Pecten inequisculptus Tiberi (teste Jeffreys).

A small, but elegantly colored and sculptured, inequivalve Pecten was taken living at station 872. This I refer doubtfully to the above-named, Mediterranean deep-water species. In our two examples the upper valve is finely and regularly cancellated, with fine radiating and concentric lines; the under valve is covered with fine, raised, concentric ribs only. Ears prominent. Color whitish and different shades of red and brown, irregularly mottled.

Pecten, sp. (near P. opercularis).

Fragments of a large and peculiar Pecten occurred at stations 873 and 874. They closely resemble, in sculpture, the P. opercularis of Europe, except that the large ribs are triangular and carinated at summit, instead of rounded. These large ribs are separated by equally wide, concave interspaces, which, like the ribs, are marked by slightly concave, radiating furrows, and the surface of these furrows is covered with thin, concentric, slightly raised, wavy plates, the waves being limited by the fine radiating ridges between the grooves. Interior of valves with broad, flat grooves, alternating with flat ribs of the same width. Color grayish white, the ribs pale reddish.

List of species enumerated in the preceding article.

[One asterisk signifies that the species is an addition to the New England or North American fauna; two, that it is a newly discovered species; E European; G = Greenlandic; M=middle region of New England, or both north and south of Cape Cod; N= northern coasts of America (Cape Cod to Labrador); 8=southern; 0=oceanic; P=North Pacific.]

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PART III.-CATALOGUE OF MOLLUSCA RECENTLY ADDED TO THE FAUNA OF SOUTHERN NEW ENGLAND.

By A. E. VERRILL.

The following lists include 130 species of Mollusca that have recently been added to the fauna of Southern New England, mainly through the researches of the dredging party of the United States Fish Commission on the steamer "Fish Hawk". The greater portion of these, with several others undetermined or not yet described, were taken on September 4 and 13 and October 2, on the outer bank or slope, 70 to 115 miles south from Martha's Vineyard and Newport, R. I., in 65 to 500 fathoms. For a list of these localities see p.

In these lists those species which were unrecorded from or entirely new to New England or to the northeastern coast of America are indicated by an asterisk; previously undescribed species by two asterisks; those known previously from our northern coasts have N prefixed; those from the middle parts of the coast have M, and are neither specially southern nor northern; those oceanic species belonging to the surface fauna have o prefixed; southern forms are designated by s; those that are also known from Europe are designated by E; those peculiar to America by A.

In the tables, living specimens are indicated by an asterisk; dead ones by a dagger; m signifies many; sv, several; r, rare; 1, unusually large; j, young.

List of Mollusca from the outer banks previously unknown south of Cape Cod.

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