Bulletin - United States National Museum - Smithsonian Institution

26 BULLETIN 96, UNITED STATES NATIONAL MUSEUM.
onychocellaria are straight, and their opesium presents a posterior
part, narrow and denticulated; the mandil)]e is composed of two
membranes. The zooecium is closed by an opercular valve. The
mural rim is not separated from the cryptocyst.
Genotype.—Onychocella solida Nordgaard, 1907.
Range.—Jacksonian-Eecent.
VELUMELLA, new genus.
{Velum., sail, in allusion to the membranes of the mandibles.)
The retractor muscles of the polypide are attached in the median
axis of the zooecium; the opesiular indentations are S3^mmetrical.
The onychocellaria are straight, without distal canal; the rachis of
the mandible bears two broad membranes; the opesium of the onychocellarium
is elliptical and entirely denticulated. The operculum
is a wholly chitinized simple one, not separable from the ectocyst.
Multiporous septulae. The mural rim is distinct from the cryptocyst.
Genotype.— Velumella {Onychocella) levinseni, new name.^
DIPLOPHOLEOS, new genus.
{Diploos, double; pholeos, den of an animal.)
The retractor muscles of the poh'pide are attached in the median
axis of the zooecium. The lateral indentations are symmetrical and
almost transformed into true opesiules. The onychocellaria are
straight, their opesium is oval, with a denticulated poster ; the mandi-
ble (onychocellium) is bimembranous. The mural rim is not separated
from the cryptocyst. The zooecium is closed by an operculum
attached to the ectocyst. The axis of rotation of the operculum is indicated
by two opesial denticles. The zooecial opesia are dimorphous
one kind is elongated and the other transverse.
Genotype.— Dipdoplioleos fusiforme., new species.
Range.—Jacksonian, Vicksburgian.
DIPLOPHOLEOS FUSIFORME, new speciea.
Plate 3, fig. 2.
Description.—The zoarium incrusts shells and pebbles. The zooecia
are hexagonal, a little elongated, separated by a narrow furrow or
united among themselves by their mural rims; the cryptocyst is
deep, concave, shorter than the opesium, finely granular; the po-
lypi dian convexity is protruding, wrinkled or granulated, denticu-
lated on its opesial border; the lateral openings are deep, round,
almost becoming true opesiules ; the opesium is elongate, semilunate,
finely crenulated. The ovicell is an inconspicuous distal convexity,
sometimes limited by two lines of lateral suture. The onychocel-
1 This new name is proposed for the recent species figured as Onychocella species by
Levinsen in his Morphological and Systematic Studies on the Cheilostomatous Bryozoa,
1909, pi. 22, figs. 3a-d.
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