NORTH AMERICAN EARLY TERTIARY BRYOZOA. 329 



In spite of the imperfections of the few specimens discovered it was interesting 

 to note this species, for it completes the geologic series in the distribution of the 

 genus. We are acquainted with Tn/postega 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.Czt, 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, hyperstomial, 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. 



[A=0.07mm. . rZs=0.3G-0.40mm. 



Measurements. Apertures, _ .., /ooecia^, nn , 



U-a=0.05 mm. Us=0.24 mm. 



Affinities. This species differs from Trypostega inornata Gabb and Horn, 

 1862, in its distinctly smaller dimensions (Z.s=0.40mm.), its frontal undulations 

 and its infra-oral gibbosity. 



It differs from Trypostega vemista 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, li miles above Bainbridge, 

 Georgia (very rare). 



Cotypes.G&i. No. 64042, U.S.N.M. 



TRYPOSTEGA INORNATA Gabb and Horn, 1862. 



Plate 44, figs. 8-10. 



1862. Ccllepora inornata GABB and HORN, Monograph Polyzoa Secondary and Tertiary 

 North America, Journal Academy Natural Science, Philadelphia, ser. 2, vol. 5v 

 p. 127, pi. 19, fig. 10. 



Description. The zoarium incrusts shells. The zooecia are elongated, distinct, 

 pyriform; the frontal is smooth and nearly flat. The aperture is formed of an 



