Bulletin - United States National Museum - Smithsonian Institution

SOUTH AFRICAN MARINE MOLLUSKS. 91
The type and two specimens, Cat. No. 250362, U.S.N.M., come
from Port Alfred (Coll. No. 1235). The type has six postnuclear
whorls, and measures: Length, 3.8 mm.; diameter, 1.8 mm.
We have seen three additional lots of this species which are in
Colonel Turton's collection, all from Port Alfred : 29 specimens (Coll.
No. 1589); 33 specimens (Coll. No. 1590); 2 specimens (Coll. No.
1599).
ODOSTOMIA (EVALEA) ACRIFA, new species.
Plate 16, fig. 3.
Shell elongate-conic, bluish white, with five equal and equally
spaced, narrow, yellowish, spiral bands, which correspond with internal
lirations. Nuclear whorls depressed helicoid, obliquely immersed in
the first of the succeeding turns, above which a very small portion of
the tilted edge of the last volution only projects. Postnuclear whorls
quite strongly rounded, narrowly shouldered at the summit, marked
by rather strong lines of growth, which have a tendency on the later
whorls to divide the surface of the shell into riblets at the shoulder,
and numerous, very fine, spiral stria tions. The posterior limit of the
interior of each whorl is seen through the texture of the shell and
gives this the appearance of having a double suture. Sutures
strongly constricted. Periphery of the last whorl inflated and
strongly rounded. Base short, conspicuously umbilicated, inflated,
well rounded, marked like the spire by lines of growth and fine spiral
lines. Aperture broadly ovate; posterior angle acute; outer Up thin,
showing five lirations within, between the posterior angle and the
periphery; inner lip curved, slightly reflected but distinct, provided
with a strong oblique fold opposite the umbilicus; parietal wall cov-
ered by a moderately thick callus.
The type, Cat. No. 250364, U.S.N.M., comes from Port Alfred
(Coll. No. 1237). It has six postnuclear whorls, and measures:
Length, 3.4 mm.; diameter, 1.4 mm.
ODOSTOMIA (ODOSTOMIA) IRAFCA, new species.
Plate 18, fig. 2.
Shell minute, translucent, yellowish white. Nuclear whorls deeply
immersed in the first of the succeeding turns, above which the tilted
edge of the last volution only projects. Postnuclear whorls inflated,
strongly rounded, appressed at the summit, marked by rather coarse
lines of growth. Sutures strongly constricted. Periphery of the last
whorl inflated and also well rounded. Base somewhat attenuated,
very slightly umbilicated, marked like the spire. Aperture broadly
oval; outer Up thin, somewhat effuse; inner lip strongly curved,
somewhat twisted, and strongly reflected, provided with a strong
parietal wall covered with
oblique fold opposite the umbilical chink ;
a thin callus.