NORTH AMERICAN EARLY TERTIARY BBYOZOA. 463 



SMITTINA EXIGUA. new species. 



Plate 59, figs. 17-19. 



Description. The zoarium is free, bilamellar with flat or undulated fronds; 

 the lamellae, back to back, are separable. The zooecia are elongated, distinct, 

 elliptical ; the frontal is convex bordered by a line of areolar pores ; the pleurocyst 

 is porous with short interareolar costules. The apertura (interior) is transverse. 

 semilunar with a proximal border very little convex; the peristomice is elongated, 

 deformed inf eriorly by the oral avicularium ; the lyrula is very small and pointed. 

 The ovicell is small, much imbedded in the distal zooecia ; the frontal area is quite 

 fragile. The median avicularium is very small, elliptical with pivot. 



-,, [Ape=0.14mm. fAa=0.12mm 



Measurements. Peristomice Apertura , 



lZpe=0.12mm. lZa=0.13.-0.14 mm. 



. [7,3=0.60-0.80 mm. 

 Zo eCia lfe=0.30-0.32mm. 



Variations. Like all the species with porous pleurocyst, this one has some 

 zooecia of quite variable aspect; even in fossilization the pores are closed and the 

 zooecia appear absolutely smooth. 



Some closed zooecia, in which the apertura is replaced by a simple pore, 

 appear quite frequently; they never have an avicularium. Their physiologic role is 

 unknown. 



Affinities. This species differs from Smittina strcmibecki Eeuss, 1865, in its 

 larger micrometric dimensions (Lz=0.6Q mm. and not 0.44 mm.), its porous and 

 not costtilar pleurocyst. and in its smaller ovicell. 



It differs from Smittina sordida in its pleurocyst, which is porous and not 

 granular, and in the absence of all frontal avicularia. 



Certain variations of PoreUa portentosa assume somewhat the aspect of this 

 species, which differs, however, in the pleurocyst and nontremocystal frontal and 

 in the nonbeaded peristome. 



Occurrence. Middle Jacksonian: Eutaw Springs, South Carolina (rare): 

 Baldock, Barnwell County, South Carolina (rare) ; 3^ miles west of Grovania. 

 Georgia (very rare) ; Rich Hill. Crawford County, Georgia (rare) ; mile south' 

 east of Georgia Kaolin Company Mine, Twiggs County, Georgia (very rare). 

 Cotypes.C&t No. 64122, 64131, TIS.N.M. 



SMITTINA STROMBECKI Reuss, 1865. 



Plate 59, figs. 12-14. 



1865. Lepralia strom'bccki REUSS, Die Foraniinifera, Anthozoen uncl Bryozoen des deutsehen 

 Septarienthones, Denkschriften der k. Akad. der wisscnschaften Wien, vol. 25, 

 Abth. 1, pi. 8, fig. 12. 



Description. The zoarium incrusts shells and bryozoa. The zooecia are small, 

 elongated, fusiform, separated by a furrow or by a salient thread; the frontal is 

 somewhat convex and bordered laterally by a line of small areolae; the pleurocyst 

 i? costular on the borders, apparently smooth in the middle, but actually porous 



