574 PROCEEDINGS OF UNITED STATES NATIONAL MUSEUM. 
Marsenina ampla Verrill, sp. nov. 
Trans. Conn. Acad., v, pl. 42, figs. 3, 3a." 
Shell broad-oval, white, nearly opaque, fragile, with conspicuous lines 
of growth, but otherwise smooth; whorls scarcely two; last whorl very 
large, constituting nearly the entire shell, and nearly concealing the first 
whorl, which appears only as a minute incurved nucleus, situated in an 
apical depression. Aperture broad, oblong-oval, showing the interior 
of the spire to the apex. Outer lip thin, distinctly expanded and slightly 
shouldered near the suture, somewhat straight along the right and left 
sides, regularly rounded in front, slightly excurved where it joins the 
inner lip, which consists of a narrow and thin coating, conformable to 
the columella surface, but with a distinct, narrow groove, and with the 
edge slightly raised as a narrow lamina in the umbilical region. The 
columella-edge is sigmoid and very much ineurved in the umbilical 
region. 
Length, 11; breadth, 8°"; depth of last whorl, 5”. 
Eastport, Me. Dredged in 1868, by the writer. 
Velutella cryptospira (Middend.). 
G. O. Sars, Moll. Reg. Arct. Norv., p. 149, pl. 21, figs 9 a-c. 
A good living example of this shell was taken by us in 1877, off Hali- 
fax, Nova Scotia, in 57 fathoms (station 82). 
The shell is very thin, translucent, yellowish horn-color, flexible, and 
but slightly calcified, with no sculpture except fine lines or growth. 
The spire is small, incurved, and depressed, so that the apical whorl is 
not visible in a front view. The aperture is elongated. The outer lip 
expands rather abruptly posteriorly, and is prolonged anteriorly. 
Length, 8™"; breadth, 5"; length of aperture, 6.5". 
Trichotropis conica Moller. 
Kroyer’s Tidss., iv, p. 85, 1812.—G. O. Sars, op. cit., p. 163, pl. 13, fig. 3. 
A single dead, but large and characteristic, specimen of this very dis- 
tinct species was taken in the Gulf of Maine, off Cape Sable, Nova Scotia, 
in 75 fathoms, by the United States Fish Commission party, on the 
“Speedwell”, in 1877. Itis easily recognized by its conical spire and its 
flattened base, covered with revolving grooves and ridges. The revolv- 
ing ribs on the spire are stronger than those on the base, and unequal. 
Rissoa (Cingula) harpa Verrill, sp. nov. 
Shell small, white, translucent, acute-conical, with five very convex, 
rounded whorls and deeply impressed sutures ; body-whorl large; api- 
cal whorl very small, smooth, regular. Sculpture very regular, well- 
raised, rounded, transverse ribs, about twenty-six on the last whorl, sep- 
arated by spaces rather wider than the ribs; and fine, close, microscopic 
spiral lines, which cover the interspaces. Aperture nearly circular, 
slightly effuse in front. Outer lip thin, regularly rounded; inner lip 
reflexed in the umbilical region, and continued on the body-whori only 
