160 
BULLETIN 106, UNITED STATES NATIONAL MUSEUM. 
from it in its hyperstomial ovicell. It is the only species of Amphiblestrum pro- 
vided with round avicularia. 
Occurrence. — Middle Jacksonian: Lenuds Ferry, South Carolina (very rare). 
Holotype. — Cat. No. 63929, U.S.N.M. 
AMPHIBLESTRUM FLAMMEUM, new species. 
Plate 29, fig. 15. 
The zoarium incrusts rocks. The zooecia are elongated, distinct, distended, 
and have a small narrow cryptocvst ; the mural rim is thin, salient, complete, encom- 
passing a concave cryptocvst shorter than the opesium. The opesium is oval or 
elliptical. The ovicell is globular, salient, hyperstomial, never closed by the oper- 
culum. The avicularia are interzooecial, much elongated, thin, and sinous in front 
like a fame, with a very small canal serving to lodge the mandible. 
M easurements. — Opesia 
ho— 0.20-0.25 mm. 
Zo=0.15-0.20 mm. 
. \Lz = 0.50—0.60 mm. 
ZiOOGCUV. r r, oa p of 
1/2 = 0.30-0.35 mm. 
.... \Lav=0A0 mm. 
Avicularia 
1 7(217=0.15 mm. 
Affinities. — The cryptocvst is very variable in this species; some zooecia are 
unprovided with one and resemble those of Collopora Gray, 1818. The relations 
between this genus and Amphiblestrum Gray, 1818. are recognized as having been 
very close. 
The ovicell on our specimens is ornamented with neither a keel nor a callosity. 
The a (Unities of this species with Callopora tenuirostris Hincks, 1880, are very great, 
but it differs from the latter in the presence of a cryptocvst in the much smaller 
orifice of the avicularium and in the much larger zooecium. 
It differs from Amphiblestrum patens in the absence of a gymnocyst, in the 
complete mural rim and in a long distal canal in the avicularium. 
Occurrence. — Middle Jacksonian (Castle Hayne limestone) : Wilmington, North 
Carolina (rare). 
Holotype.- — Cat. No. 63930, U.S.N.M. 
AMPHIBLESTRUM PATENS, new species. 
Plate 30, figs. 1-3. 
The zoarium incrusts shells. The zooecia are distinct, slightly elongated, tyide, 
often having a small gymnocyst; the mural rim is enlarged laterally and incom- 
plete proximally; the cryptocyst is a little concave, distinct from the mural rim, 
granular. The opesium is terminal, elongated, oval, finely crenulated, with a 
straight proximal border. The ovicell is hyperstomial, never closed by the oper- 
culum. The avicularia are interzooecial, elongated, fusiform, wide , with a short 
distal, small canal ; the pivot is formed by two lateral denticles. The ancestrula 
is a small, ordinary zooecium. 
