NORTH AMERICAN EARLY TERTIARY BRYOZOA. 
579 
\ 
On the well-preserved specimens (notably those from Wilmington), by inclining 
the preparation, we can see in the peristomie two or three salient denticles of whose 
physiologic significance we are ignorant. 
The frontal is often smooth (fig. 17). 
The orifice of the ovicelled zooecia has somewhat the aspect of a human mouth 
opened to yawn. 
Affinities. — This species is distinguished from PengastreUa elegans by its large 
general dimensions and the absence of three rows of areolar pores. 
It is distinguished from PerigastreUa ovoidea in the elliptical form of its 
zooecia, its lesser zooecial length {Lz— 0.70 and not 0.80 mm.), its less convex 
frontal, its wider and larger ovicell with two quite visible lamellae. 
It is distinguished from PerigastreUa. plana in its smaller micrometric dimen- 
sions (fe=0.40 and not 0.50-0.60 mm.) and in its pleurocyst, which is complete 
instead of being lateral only. 
Occmrence. — Lower Jacksonian (Mooclys marl) : Jackson, Mississippi (rare). 
Middle Jacksonian: Wilmington, North Carolina (common); 31 miles south 
of Perry, Georgia (rare) ; 12 miles southeast of Marshallville. Georgia (rare) ; Rich 
Hill, Crawford County, Georgia (rare) ; Eutaw Springs, South Carolina (rare) ; 
one-half mile southeast of Georgia Kaolin Company Mine, Twiggs County, Georgia 
(rare) ; 17 miles northeast of Hawkinsville, Georgia. 
Upper Jacksonian (Ocala limestone) : West bank of Scpulga River, Escambia 
County, Alabama (rare) ; old factory, 14 miles above Bainbridge, Georgia (rare). 
Cotypes. — Cat. No. 64196, U.S.N.M. 
PERIGASTRELLA ELEGANS, new species. 
Plate 73, fig. 1. 
Description. — The zoarium incrusts shells. The zooecia are distinct, a little 
elongated, small, elliptical ; the frontal is convex and surrounded by two or three 
rows of round or triangular areolar pores; it is formed of a very finely granular 
pleurocyst. The apertura is deep, trapezoid ; the peristome is corn])] etc, thin, salient ; 
its inferior lip is a very salient mucro, hiding somewhat the. apertura or depressed 
on the frontal. The ovicell is very small, little salient, and formed of a pleurocyst 
and an olocyst which are distinct from each other. 
Measurements. — Apertura 
(A<z=0.08 mm. 
17<7=0.10 mm. 
Zooecia 
I 7,2=0.55 mm. 
172=0.30-0.35 mm. 
Affinities. — This elegant species much resembles PerigastreUa oscitans in the 
absence of decided characters and appears to be a minor variety of it. It differs 
from it in its much smaller micrometric dimensions, less than 0.55 mm., in its 
smoother ovicell, and its three rows of areolar pores. 
Occurrence. — Middle Jacksonian: Baldock, Barnwell County, South Carolina 
(rare). 
Holotype.— Cat. No. 64197, U.S.N.M. 
