Bulletin - United States National Museum - Smithsonian Institution

SOUTH AFRICAN MARINE MOLLUSKS. 99
dered sinuous by the external sculpture, translucent, showing the
external sculpture within; columella covered by a thick callus which
is reflected over the parietal wall and renders the peritreme com-
plete.
The type, Cat. No. 250350, U.S.N.M., comes from Port Alfred (Coll.
No. 1223). It has 11^ whorls and measures: Length, 12 mm.; diameter,
3.5 mm.
TRIPHORIS CONVEXA Smith.
Cat. No. 186805, U.S.N.M., one specimen from Port Alfred (Coll.
No. 171). Cat, No. 227724, U.S.N.M., four specimens from the same
source (Coll. No. 819). Cat, No. 227725, U. S.N.M., four specimens
also from Port Alfred (Coll. No. 820).
TRIPHORIS, species ?
Cat, No. 250347, U.S.N.M., contains a young individual of a pure
white species from Port Alfred, which differs from any of the known
species, but is too young to serve for a diagnosis. (Coll. No. 1220).
TRIPHORIS HELENA, new species.
Plate 11, figs. 2, 5.
Shell elongate-conic, bluish white. Nuclear whorls almost four;
the first third of a turn smooth, the succeeding marked by two strong,
lamellar spiral cords, the first of which is at the summit and the second
about as far above the suture as it is separated from the first. Post-
nuclear whorls strongly rounded, ornamented with three strong, sub-
lamellar spiral cords which are feebly tuberculated. The first of these
cords is at the summit, the third about as far above the suture as it is
separated from the median, while the median occupies the space midway
between the other two. In addition to these spiral cords, the whorls
are marked by about 20 obsolete, broad riblets which render the
spiral cords feebly tuberculated. In addition to the above sculp-
ture, the entire surface is marked with fine lines of growth and micro-
scopic, spiral striations. Suture channeled. Periphery of the last
whorl marked by a broad spiral sulcus which is equal to the sulcus
separating the supraperipheral cord from the median cord. This
sulcus is bound anteriorly by a cord equal to those on the spire, a
second feeble spiral cord- is situated at the insertion of the columella,
the space between these two being a broad, concave area. Aperture
decidedly channeled anteriorly, feebly so posteriorly; outer lip thin,
showing the external sculpture within, rendered sinuous at the edge
by the external sculpture; columella stout, covered with a, strong
callus which extends over the parietal wall and renders the peritreme
complete.
Cat. No. 250348, U.S.N.M., contains the nuclear tip of a young specimen,
and an adult specimen, minus the nucleus. These may be con-
m