Bulletin - United States National Museum - Smithsonian Institution

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BULLETIN m, UNITED STATES NATIONAL MUSEUM.
laterally two areas in the form of a lunar crescent and more or less
perforated. There are nearly always some spines and some avicularia.
Genotype.—Hipyortienella {Lepralia) mucronelliformis Waters,
1899.
Range.—Lutecian-Eecent.
HIPPOZEUGOSELLA, new genus.
{Ilippos^ horse, in reference to the horseshoe form of the aperture
zuegos^ a pair, referring to the arrangement of the zooecia.
The ovicell is hyperstomial, its orifice is large, without rapport
with the operculum, and is closed by a special membrane. The aper-
tura is elliptical; two small cardelles separate the anter from the
somewhat smaller poster. The frontal is a tremocyst with small
pores. The zoarium is free; the zooecia are joined two by two. No
spines. Avicularia present.
Genotype.—Hippozeugosella {Bactridiifm) hagenowi Eeuss IS-il.
Range.—Priabonian-Miocene.
HIPPOZEUGOSELLA TEGES, new species.
Plate 4, fig. 5.
Description.—The zoarium is free, erect, unilamellar, formed of
two longitudinal rows of zooecia ; on the dorsal the zooecia are con-
vex, alternate, and have the aspect of a mat. The zooecia are dis-
tinct, elongate, hexagonal; the frontal is convex and formed of a
tremocyst with very small pores. The apertura is orbicular and
formed of a large anter, and Avith a smaller poster separated by
two very small cardelles; the peristome is complete, broad, and
infundibuliform. On the peristome itself and near the zoarial axis
there is a small round avicularium provided with a pivot. Ovicell?
i,r , » X \ha=0.\l mm.
Measurements.—Aperture -, _ .
^
^
[ la— 0.11 mm.
0.70-0.75 mm.
\ Is =0.4:0 mm.
. fZ3=
Zooecia -, „ .„
Affinities.—The frontal pores are very small and are easily filled
up. The frontal and the dorsal are covered with very small granu-
lations. The formation of the, branches is effected by the union of
two zooecia arising from two superposed zooecia.
Occurrence.—Upper Jacksonian (Zeuglodon zone) ; Cocoa post
office, Choctaw County, Alabama (very rare).
Upper Jacksonian (Ocala limestone) : Chipola River, east of Marianna,
Jackson County, Florida (common).
Type.—Cat. No. 62591, U.S.N.M.
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