Bulletin - United States National Museum - Smithsonian Institution

122 BULLETIN 91, UNITED STATES NATIONAL MUSEUM.
terior angle decidedly obtuse; outer lip thin, showing the external
sculpture within, which renders the outer lip sinuous at the edge;
columella oblique, very thin, and slightly revolute.
The type, Cat. No. 250396, U.S.N.M., comes from Port Alfred (Coll.
No. 1269). It has seven postnuclear whorls, and measures: Length,
2 mm. ; diameter, 0.7 mm.
Genus DIALA A. Adams.
DIALA INFRASULCATA Sowerby.
Three specimens, Cat. No. 187070, U.S.N.M., from Port Alfred
(Coll. No. 608). Cat. No. 187071, three specimens from Port Alfred
(Coll. No. 609).
DIALA AFRICANA, new species.
Plate 6, fig. 1.
Shell elongate-conic, subdiaphanous. Nuclear whorls scarcely
differentiated from the postnuclear turns. Postnuclear whorls
strongly rounded, marked by numerous lines of growth and exceed-
ingly fine spiral striations; the summits of the whorls are appressed
to the preceding turns and allow these to shine through them, which
gives the shell the aspect of having a double suture; sutures strongly
constricted. Periphery of the last whorl somewhat inflated, well
rounded. Base broadly umbilicated, well rounded, marked like the
spire. Aperture large; outer Up thin, translucent; inner lip free,
strongly curved, and somewhat reflected over the umbilicus; parietal
wall glazed by a thin callus.
The type, Cat. No. 187063, U.S.N.M., comes from Port Alfred
(Coll. No. 601). It has seven and one-half whorls, and measures:
Length, 4.8 mm.; diameter, 2.1 mm.
The following specimens from Port Alfred are in the collection of
the United States National Museum: Cat. No. 187067, one specimen
(Coll. No. 605). Cat. No. 227746, three specimens (Coll. No. 841).
Cat, No. 249722, two specimens (Coll. No. 994). Cat. No. 250424,
three specimens (Coll. No. 1297). Cat. No. 250434, two specimens
(Coll. No. 1307). In addition to these I have seen two lots, also from
Port Alfred: (Coll. No. 1599), two specimens and (Coll. No. 1593), 30
specimens, which were returned to Colonel Turton.
DIALA DUBIA Sowerby.
The United States National Museum has seven lots of this species
from Port Alfred. Cat. No. 186812, 5 specimens (Coll. No. 178).
Cat. No. 187060, 2 specimens (Coll. No. 598). Cat. No. 187464,
1 specimen (Coll. No. 602). Cat. No. 187065, 2 specimens (Coll.
No. 603). Cat. No. 227744, 3 specimens (Coll. No. 839). Cat. No.
249725, 2 specimens (Coll. No. 997). Cat. No. 250430, 2 specimens
(CoU. No. 1303). Cat. No. 250433, 2 specimens (Coll. No. 1300).
Cat. No. 252202, 15 specimens (Coll. Nos. 1591 and 1597). (In addi-