NORTH AMERICAN EARLY TERTIARY BRYOZOA. 
577 
PEKIGASTRELLA HEXAGONALIS, new species. 
Plate 72, fig. 10. 
Description . — The zoarium inerusts bryozoa. The zooecia are large, distinct, 
hexagonal; the frontal is little concave and surrounded by a double row of quite 
crowded areolae ; it is formed of a granular pleurocyst. The apertura is transverse, 
oblique, trapezoid, little visible exteriorly; the peristome is little salient, oblique 
with an inferior lip in the form of a mucro, which is elevated and prominent. The 
ovicell is small, transverse, globular, granular; it is hyperstomial and recumbent. 
Measurements . — Apertu ra 
| Aa=0.08-0.10 mm. 
lte=0.1fmm. 
Zooecia 
jLz= 0.80 mm. 
|/s=0.70-0.80 mm. 
Occurrence . — Middle Jacksonian (Castle Hayne limestone) : Wilmington, 
North Carolina (rare). 
Holotype. — Cat. No. 64193, U.S.N.M. 
PERIGASTRELLA RHOMBOIDALIS, new species. 
Plate 72, fig. 11. 
Description . — The zoarium is bilamellar; the two lamellae, back to back, are 
inseparable. The zooecia are distinct, large, elongated, rhomhoidal ; the frontal 
is convex, surrounded by a double line of small triangular areolae and formed of 
a finely granular pleurocyst. The peristomice is semilunar, transverse, complete, 
with a concave proximal border; the peristome is thin, sharp, little salient. The 
ovicell is small, transverse, little salient, finely granular; it is always closed by the 
operculum. 
f/ta=0.16mm. „ . 1X3=1.00-1.20 mm. 
24mm. Zooec,a b=0.60-0.80mm. 
M easurem,ents . — Apertura , ' . ' „ 
l la— 0.22-0. 
Affinities . — The figured specimen only lias been found. It appears to repre- 
sent a type rather divergent in the genus. We believe in making a new genus only 
when the material is sufficient. 
Occurrence . — Middle Jacksonian (Castle Havne limestone) : Wilmington, 
North Carolina (very rare). 
Holotype. — Cat. No. 64194, U.S.N.M. 
PERIGASTRELLA CYCLORIS Gabb and Horn, 18G2. 
Plate 72. figs. 12-14. 
1862. Cellepora cycloris Gabb and Horn, Monograph Polyzoa Secondary and Tertiary forma- 
tions of North America, Journal Academy Natural Sciences, Philadelphia, ser. 2, 
vol. 5, p. 127, pi. 19, fig. 9. 
1890. Cellepora cycloris De Gregorio, Monograph Fauna Eocenique de P Alabama, Annales 
Geologie et Paleontologie, Livr. 7 and 8, p. 247, pi. 43, fig. 1. 
Description .— The zoarium incrusts shells and bryozoa. The zooecia are dis- 
tinct, large, hexagonal; the frontal is very convex and surrounded by a triple 
row of very small areolae; it is formed of a smooth or very finely granular pleu- 
55899— 19— Bull. 106 37 
