NORTH AMERICAN EARLY TERTIARY BRYOZOA. 
329 
In spite of the imperfections of the few specimens discovered it was interesting 
to Rote this species, for it completes the geologic series in the distribution of the 
genus. We are acquainted with Trypostega species from the Lutetian of southern 
France and Trypostega aquitanica Canu, 1906, from the Stampian of southern 
France. 
Occurrence. — Wilcoxian (Bashi formation): Woods Bluff, Alabama (rare). 
Holotype. — Cat. No. 63836, U.S.N.M. 
TRYPOSTEGA UNDULATA, sew species. 
Plate 44, figs. 6, 7. 
Description.- — The zoarium incrusts shells and bryozoa. The zooecia are small, 
distinct, elongated, pyriform; the frontal is convex, ornamented with transverse 
undulations and often with an infra-oral gibbosity, and unprovided with visible 
pores. The ovicell is elongated, prominent, smooth, globular, liyperstomial, and 
always closed by the operculum. The aperture is semilunar; the proximal border 
is straight and bears a large rectangular rimule. The zooeciules are small, elliptical, 
perforated by a very small circular orifice. 
Measurements. — Aperture 
|Au= 0.07 mm. 
l7a.=0.05 mm. 
Zooecia 
\Lz— 0.36-0.10 mm. 
lZs=0.24 mm. 
Affinities. — This species differs from Trypostega inornata Gabb and Horn, 
1862, in its distinctly smaller dimensions (ZA=0.40 mm.) , its frontal undulations 
and its infra-oral gibbosity. 
It differs from Trypostega venusta Norman. 1864, in its smooth, nonporous 
frontal and its smaller oral dimensions. 
It differs from Trypostega aquitanica Canu, 1906, of the French Stampian, 
in the absence of a distally much developed peristome. 
Occurrence. — Middle Jacksonian: Rich Hill 5J miles southeast of Knoxville, 
Georgia (rare) ; 18 miles west of Wrightsville, Georgia (rare) ; Baldock, Barnwell 
County, South Carolina (rare). 
Upper Jacksonian (Ocala limestone) : Near Georgia Kaolin Company’s mine, 
Twiggs County, Georgia (very rare) ; Old Factory, 14 miles above Bainbridge, 
Georgia (very rare). 
Cotypes. — Cat. No. 64042, U.S.N.M. 
TRYPOSTEGA INORNATA Gabb and Horn, 1862. 
Plate 44, figs. 8-10. 
1862. Cellepora inornata Gabb. and Hobn, Monograph Polyzoa Secondary and Tertiary 
North America, Journal Academy Natural Science, Philadelphia, ser. 2, vol. Si, 
p. 127, pi. 19, fig. 10. 
D escription. — The zoarium incrusts shells. The zooecia are elongated, distinct, 
pyriform; the frontal is smooth and nearly flat. The aperture is formed of an 
