Bulletin - United States National Museum - Smithsonian Institution

36 BULLETIN m, UNITED STATES NATIONAL MUSEUM.
ACANTHOCELLA ERINACEA. new species.
Plate 4, fig. 1.
Description.—The zoarium incrusts shells and bryozoa or creeps
over algae. The zooecia are distinct, very slightly elongated, sub-
circnlar; the frontal is very convex; the costules are thick, separated
by the lacunae, ornamented by three, very prominent, hollow spines
corresponding to the lumen pores. The apertura is semilunar with
a straight proximal border; the peristome is distal and bears four
large, hollow spines. The ovicell is hyperstomial, buried in the distal
zooecia, globose, not closed by the operculum, ornamented with small,
remote punctations.
,, ^ . ^ \ha=O.Od mm.
Measurements.—Aperture { , ,. ^ ^ ,. ^ ^
^ 1^=0.11-0.12 mm.
Zooecia ,
fZs=0.75-0.80 mm.
,
Z2!=0.o0-0.6o
n -n n^- mm.
Variations.—The sharp points which decorate this species give it
the spinous aspect of the hedge hog. It is very variable in its micro-
metrical dimensions and its gemmation; the zooecia are oriented in
the most unexpected and divergent manner.
Occurrence.—Middle Jacksonian (Castle Hayne limestone) : Wil-
mington, North Carolina (rare).
Type.—C2ii. No. 62587, U.S.N.M.
CRIBRENDOECIUM, new genus.
(Abbreviation of " Cribrilina with endozocecial ovicell.'')
The ovicell is endozocecial. The costules are separated by a small
initial slit and some medium sized lacunae ; they have no lumen pores.
The apertura is formed of a semilunar anterior portion and a larger
and concave posterior part separated by two cardelles. The apertura
of the ovicelled zooecia is larger. Large interzooecial avicularia are
present.
Genotype.—Crihrendoeciuni tenuicostulatum, new species. Jack-
sonian.
CRIBRENDOECIUM TENUICOSTULATUM, new species.
Plate 4, tig. 2.
Description.—The zoarium incrusts shells. The zooecia are dis-
tinct, elongated, separated by a furrow, elliptical, fusiform; the
frontal is convex ; the costules are very thin, niuiierous, without lumen
pores, and separated by very small lacunae. The aperturae of the
ordinary zocecia are formed of a semilunar anterior and a verj^ large,
straight posterior part separated by two small cardelles; the aper-
tura of the ovicelled zocecia is larger and its posterior portion is