Bulletin - United States National Museum - Smithsonian Institution

130 BULLETIN 91, UNITED STATES NATIONAL MUSEUM.
The type, Cat. No. 187669, U.S.N.M., comes from Port Alfred
(Coll. No. 607). It has almost four postnuclear whorls and measures:
Length, 2.3 mm. ; diameter, 1.5 mm. Cat. No. 249704 U.S.N.M., con-
tains another specimen from Port Alfred (Coll. No. 976).
Genus RISSOINA Orbigny.
RISSOINA ALFREDI Smith.
Cat. No. 186816, U.S.N.M., two specimens from Port Alfred (Coll.
No. 182).
RISSOINA CALIA, new species.
Plate 5, fig. 1.
Shell elongate-conic, bluish white. Nuclear whorls decollated.
Postnuclear whorls moderately rounded, strongly appressed at the
summit, which lends them a somewhat curved outline near the
summit; marked with numerous, very regular, slender, flexuous
axial ribs, of which 26 occur upon the first, 32 upon the second, 36 upon
the third and fourth, 40 upon the fifth, and 46 upon the penultimate
turn. The moderately impressed spaces enclosed between these ribs
are about as wide as the ribs, and are crossed by slender spiral threads,
of which about 13 occur between the sutures. The spaces enclosed
between the spiral threads and the axial ribs are a little wider
than the spiral threads and appear as well-impressed pits. Periph-
ery of the last whorl Avell rounded. Base somewhat prolonged,
well rounded, marked by the continuations of the axial ribs, which
become somewhat enfeebled anteriorly and 16 spiral threads;
the latter are a little more accentuated on the anterior portion than
they are upon the spire. Aperture irregularly ovate, somewhat
channeled anteriorly; posterior angle acute; outer lip moderately
thick, showing the external sculpture within; inner lip scarcely
differentiated from the body whorl, to which it is appressed; parietal
wall covered with a thin callus.
The type, and four specimens, Cat. No. 186817, U.S.N.M., come
from Port Alfred (Coll. No. 183). The type has seven postnuclear
whorls, which measure : Length, 6.7 mm. ; diameter, 2.2 mm. Cat. No.
227738, U.S.N.M., contains 10 specimens from the same locality
(Coll. No. 833), and Cat. No. 227739, contains six specimens from
the same source (Coll. No. 834).
Cat. No. 249707a, U.S.N.M., contains a badly worn specimen
(Coll. No. 979).
RISSOINA, species?
Cat. No. 249696, U.S.N.M., contains a badly worn specimen of a
small species from Port Alfred, having closely spaced, decidedly
protractive ribs and without spiral sculpture. It is too badly worn
to serve for a proper diagnosis (Coll. No. 968).