Bulletin - United States National Museum - Smithsonian Institution

150 BULLETIN 91, UNITED STATES NATIONAL MUSEUM.
last. The open umbilicus is likewise marked with slender spiral
threads. In addition to the spiral sculpture, the entire surface of
the shell is marked by numerous, retractively slanting, slender, raised,
axial threads, which are almost lamellar and are about one-fourth
as wide as the spaces that separate them; of these, about 65 occur on
the last turn. These threads run up on the sides of the strong spiral
keels, and may pass over them; in our specimen the keels are too
worn to determine this point. The axial sculpture is equally strong
on the spire and the base and even bends into the umbilicus. Aper-
ture very oblique, subcircular; outer lip rendered angulated by the
spiral cords; inner lip strongly curved and slightly reflected.
The type, Cat. No. 250500, U.S.N.M., comes from Port Alfred
(Coll. No. 1373). It has four whorls, and measures: Altitude, 4.7
mm.; greater diameter, 4.8 mm.
Family TROCHIDAE.
Genus CLANCULUS Montfort.
CLANCULUS MINIATUS Anton.
Cat. No. 134, U.S.N.M., contains one specimen collected by William
Stimpson on the North Pacific Exploring Expedition, at Simons
Bay, Cape of Good Hope. Cat. No. 18753, U.S.N.M., five specimens
.from Cape of Good Hope. Cat. No. 43096, U.S.N.M., four specimens
from the Cape of Good Hope. Cat. No. 186871, U.S.N.M., eight
specimens from Port Alfred (Coll. No. 241). Cat. No. 187104,
U.S.N.M., one specimen from the same locality (Coll. No. 649).
CLANCULUS ALFREDENSIS, new species.
Plate 23, figs. 10, 11, 12.
Shell broadly conic, rose colored, obscurely clouded with brown.
The first turn of the nucleus is strongly rounded and smooth, the
next is marked by three strong, spiral keels which divide the spaces
between the sutures into four equal parts. On the next whorl a
fourth keel makes its appearance between the summit and the
first keel anterior to it. On this whorl, the lines of growth assume
the form of slender threads. The post-nuclear whorls are marked
by two strong angles, one of which is at the periphery and the other
half-way between this and the summit. Each of these angles bears
a strong tuberculated cord. Between the median angle and the
summit of the whorls two tuberculated spiral cords occur upon the
first turn, three on the second, and four upon the last, the cord at
the summit having the strongest tubercles in each instance. Between
the peripheral cord and the median there is a faint thread upon
the first whorl, three nodulous cords on the second, of which the
median is the strongest, and five on the last. All of these cords are