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216 MOLLUSCA FROM MIOCENE AND LOWER PLIOCENE OF VIRGINIA AND NORTH CAROLINA
interior; lirae about 8 on the later whorls of the spire,
3 or 4 times as many on the body ; the 4 to 6 spirals at the
base of the body broader and more elevated than those
behind them. Axial sculpture restricted to incrementals
and more or less exaggerated resting stages. Suture
distinct, impressed. Aperture slightly expanded
anteriorly. Outer lip thickened, dentate within. Columella
excavated at the base of the body, rugose. Parietal
wall washed with enamel but so thinly that the
spiral sculpture n1ay be imperfectly concealed. An-
. terior fasciole swollen, closely lirate. Anterior canal
short, recurved, deeply en1arginate.
Scomia Jwdgii Conrad is the sole representative of
the genus within the Virginia and North Carolina
Tertiary. It is readily isolated by its heavy shell,
stocky outline, uniform spiral sculpture, and denticulate
outer and rugose inner lip.
Mansfield reports the species in Florida, from both
the Ecphora zone in the middle of the Choctawhatchee
formation and from the (} ancell aria zone at the top
of it.
Distribution: North Carolina: Duplin marl, Natural 'Veil,
Duplin County; 1% miles northeast of Fairmont (Ashpole),
Robeson County; Cape Fear Riyer, (Emmons).
. Outside distribution: Miocene, Duplin marl of Sumter County
and the Pee Dee River, Florence? County, S. C.; Jackson Bluff,
Leon County; Alum Bluff (upper bed), Liberty County, Fla.
Family COL UBRARIDAE
Genus COLUBRARI-4 Schumacher
1817. Oolubraria Schumacher, Essai d'un nouveau systeme des
vers testaces, p. 251.
Type by subsequent designation (Herrmannsen, Indicis generum
malacozoorum, primordia, vol. 1, p. 270, 1847) : Mttre:c
maculos?ts Gmelin=Buccinum 11wculosum Chemnitz. Recent,
in the Indo-Pacific region.
Shell of moderate dimensions, rather thick and solid.
Spire elevated, the axis commonly arcuate. Whorls
broadly convex, increasing slowly in diameter. Sculpture
retieulate or granular, with occasional axial varices.
Aperture shorter than the spire, narrow, obliquely lenticular.
Outer lip varicose, dentate within. Inner lip
concave. Parietal and pillar wash heavy. Anterior
canal short, recurved with parallel, proximate margins.
No name has been found for the small group of warm
water Tertiary and Recent species from the southeastern
Gulf Province and the West Indies. They have in
common and distinct from 0 olubraria s. s. a small,
slender, delicate shell tapering anteriorly into a canal
decidedly longer than that of the type of the genus;
a narrow lobate aperture, the outer margin varicose
·but not denticulate, the inner parietal wall and pillar
washed with a smooth but heavy callus. Oolubraria
lanceolata (Menke) , the Recent species, is even more
slender and elegant than the Tertiary forms and the
anterior canal more sharply defined.
Colubraria aclinica Tucker and Wilson
Plate 29, figures 5, 6
1933. Oolubraria aclinica Tucker and Wilson, Bull. Am. Paleon·
tology, vol. 18, No. 66, p. 70 (8), pl. ll (2), fig. 14.
Shell small, whorls somewhat inflated, sutures impressed.
Early whorls? Spiral sculpture of about· eight or nine primary
threads, interspaces on body whorl have a less strong .secondary
between weak tertiary threads. On the whorls of the spire only
the single secondary is present. Axial threads about the same
size as the primary spirals: At their intersection they form low
beads. Axials become obsolete toward the base. Aperture slender;
margin of the inner lip elevated to form a thin lamella.
Outer lip varical, internally carries faint lirations arranged
in pairs. Anterior canal sharply recurved; columella smooth ..
Dimensions of holotype.-Height 14, diameter 5 mm.
This species differs from 0. {lo1·idana Tucker and Wilson (Bull.
Am. Pal., vol. 18, No. 65, p. 11, pl. 4, figs. 3, 4) in not having
strong axial ribs as well as in the character of the spira.l
sculpture.
Age.-Miocene?
Locality.-Acline, Fla.-Tucker and Wilson, 1933.
The following description was drawn up from a less
. imperfect specimen (U.S.N.M.114089) fron1 the Duplin
marl, Duplin County, N.C.:
Shell small for the genus, thin, delicate, very
slender and fusiform. Body whorl a little less than
two-thirds, and aperture almost one-half the total
height. Spire elevated, tapering gracefully to a flattened
apex. Whorls probably about 7 in number; those
of the spire feebly inflated at the periphery. Body whorl
broadly rounded, attenuated anteriorly. Protoconch
smooth except for incrementals, thrice-coiled; initial
volution wound in a single plane, thus producing the
flattened apex; second whorl rounded posteriorly, but
increasingly compressed anteriorly; final turn only
feebly convex. Both axial and spiral sculpture
abruptly initiated at the beginning of the conch. Axial
sculpture of 2 or 3 obtuse varices, and 20 to 30 narrow,
rounded, moderately elevated riblets, n1ore or less irregular
in size and spacing, approximately uniform
in strength from suture to suture, evanescent at the
base of the body whorl. Spiral sculpture of low, flattened
fillets, much more regular in size and spacing than
the axials and overriding though not nodulating them;
priniaries 6 to 8 on the whorls of the spire; occasional
linear or sublinear secondaries intercalated miqway
between the primaries; spirals on body whorl broader
and relatively lower than on the spire; secondaries more
prominent relatively and absolutely, often scarcely less
wide than the primaries; an occasional tertiary introduced
in the interspaces. Incrementals on the otherwise
unsculptured areas regular and crowded, visible
under high magnification as a finely filamented grating.
Suture line distinct, impressed, finely crenulated by the
axials of the succeeding whorl. Aperture narrow,
lenticular. Outer lip subvaricose, the edge sharp and
often feebly crenulated in harmony with the spirals,
nonlirate within. Inner lip broadly excavated, re-