Bulletin - United States National Museum - Smithsonian Institution

EARLY TERTIARY CHEILOSTOME BRYOZOA. 61
continued into an expansion which forms a partial partition between
the ovicell and the zooecium; uniporous septulae; no peris-
tome." (Levinsen, 1909.)
Genotype,— IlippoiJodina {Lepralia) feegensis Busk, 1884.
Range.—Jacksonian-Recent.
HIPPOPODINA VIBRACULIFERA, new Bpecies.
Plate 5, fig. 8.
Description.—The zoarium is free, biLamellar; the two lamellae
back to back are easily separated. The zocecia are elongated, large,
hexagonal; the frontal is convex and formed of a tremocyst with
very numerous pores placed on a very finely perforated olocyst from
which it is separable. The apertura is formed of a very large orbicular
anter and of a narrower poster with proximal lip straight and
denticulated; the vestibular arch is clearly visible. The endozooecial
ovicell is immense and takes the place of a zooecium; it is convex
and perforated with tremopores; the apertura of the ovarian zocecia
is much larger. Two auriculate vibracula are placed symmetrically
on the distal part of the zocecia.
1^/7=0.25 mm.
MeasuveTnents.—Apertura of ordinary zooecia j ^__q 28 jj^ni.
|7m=:0.25mm.
Apertura of ovarian zocecia [ ^^—-q 35 mm
IZs=0.90-1.10mm.
Zocecia I ?2=0.80-1.00mm.
Occurrence.—Middle Jacksonian: Wilmington, North Carolina
(common).
Upper Jacksonian (Ocala limestone) : Old factory, 1^ miles above
Bainbridge, Georgia (rare).
Type.—C^t No. 6260-1, U.S.N.M.
Genus METRARABDOTOS Canii, 1914.
1914. Mctrarahdotos Canu, Les Bryozoires fossiles Sud-Ouest France. Bul-
letin Societe Geologique France, ser. 3, vol. 14. p. 472.
The ovicell is endozooecial. The apertura is semilunar, with a
rimule and lyrule. The frontal is surrounded with lateral areolae
and formed of an olocyst surmounted by a pleurocyst.
Genotype.—Metrarabdotos {Eschara) moniliferum Milne-Ed-
wards, 1838.
Range.—Priabonian-Astian,
The genotype is a common and characteristic Yicksburgian fossil
of the Southern States.