112 PROCEEDINGS OF THE NATIONAL MUSEUM vol.77 



Genus PALEOPOLYMORPHINA Cushman and Ozawa, new genus 



Test with the early chambers spiral, later ones becoming biserial. 

 Genotype. — P. pleurostomelloides (Franke). 



PALEOPOLYMORPHINA PLEUROSTOMELLOIDES (Franke) 



Plate 28, figures 5 a, b 



Polymorphina pleurostomelloides Franke, Abhandl. d. preuss. geol. Landes- 

 anstalt, vol. 3, 1928, p. 121, pi. 11, fig. 11. 



Test small, more or less cylindrical, tapering toward the initial end; 

 chambers initiated, oval, but little embracing, alternating, arranged 

 in an entirely biserial series, each succeeding chamber much farther 

 removed from the base; sutures oblique, much depressed, distinct; 

 wall smooth; aperture radiate. 



The present species quite recently has been described by Franke 

 from the lower Cenomanian marl of Tecklenburg, a locality from 

 which we obtained foraminiferal material from the original author 

 and found three specimens. They are very similar to Pleurosto- 

 mella, excepting for the radiate aperture. Its development is evi- 

 dently a biserial one from a spiral ancestry, and as such we have 

 erected a new genus for it and the following species. 



Distribution. — Germany, lower Cenomanian, Tecklenburg, West- 

 phalia, near the brickyard of HoUenberg, where it is not rare. 



PALEOPOLYMORPHINA GAULTINA (Berthelin) 



Plate 28, figures 6 a, 6 



Polymorphina gaultina Berthelin, Mem. Soc. G6ol. France, s6r. 3, vol. 1, 

 1880, p. 58, pi. 4, figs. 19 a-c. 



Test small, more or less compressed, fusiform, acute at both ends; 

 chambers few, the lasi> two much larger than the earlier ones, em- 

 bracing, arranged in a biserial series, each succeeding chamber 

 removed from the base; sutures but little depressed, distinct; wall 

 smooth; aperture radiate. 



Paleopolymorphina gaultina is one of the smallest species among 

 the PoJymorphinidae. The test is generally composed of five cham- 

 bers, of which the last two are much enlarged. It is a well-defined 

 species and can be easily distinguished from any other. 



Distribution. — Berthelin described it from the Lower Cretaceous 

 (Albian) of France. We have several specimens from the Gault of 

 Folkestone, England. 



