Bulletin - United States National Museum - Smithsonian Institution

SOUTH AFRICAN MARINE MOLLUSKS. 5
Genus VOLVULA A. Adams.
VOLVULA, species?
Cat. No. 250583, U.S.N.M., contains one specimen of this genus,
from Port Alfred, which unfortunately has lost part of the lip, which
renders positive identification impossible. (Coll. No. 1456).
Family SCAPHANDRIDAE.
Genus CYLICHNA Loven.
CYLICHNA AFRICANA, new species.
Plate 1, fig. 8.
Shell, white, subcylindric, spire deeply sunken, giving the apex a
perforate appearance. The body whorl is somewhat contracted in the
middle, rendering the outline of the sides concave. The entire surface
is marked by slender, subequally spaced axial riblets, which give it
a finely fluted appearance. Aperture long, narrow posteriorly,
roundly expanded anteriorly; outer lip parallel to the parietal wall
except at the expanded basal fourth of the shell. The outer lip projects
considerably above the summit of each preceding turn, marking
the highest elevation of each turn. The parietal wall of the last turn
is covered with a thin callus, which is continued posteriorly to form
the parietal wall of that part of the aperture which projects above
the summit of the preceding turn. The outside of the parietal wall
within the perforated top, is marked by the continuations of the
riblets. Columella with an inconspicuous oblique twist near the
middle, short, slender, finely curved, connected at the base with the
parietal callus.
The type and three specimens, Cat. No. 187147, U.S.N.M., were
collected at Port Alfred (Coll. No. 694). The type measures: Length,
3.4 mm.; diameter, 1.4 mm.
This species resembles Cylichna hoernesi Weinkaufffrom the Mediter-
ranean. It is, however, a little less contracted posteriorly, has the
outer lip extending much higher posteriorly, and lacks the fine stri-
ations of the spire as well as the strongly incised spiral lines of the
base.
CYLICHNA TUBULOSA Gould.
Plate 3, fig. 5.
Cylichna tubulosa Gould, Proc. Bost. Soc. Nat. Hist., vol. 7, p. 40, 1859.
Shell cylindric, a very little wider anteriorly than posteriorly, white
or creamy yellow. Spire submerged and covered; posterior end
slightly concave, the highest portion being in line with the backward
continuation of the outer lip. Left outline of the body whorl almost
straight, curving gently toward either end. Inner lip quite evenly
80737°—Bull. 91—15 2