182 FORAMINIFERA 



Genus VALVULINELLA Schubert, 1907 

 Plate 23, figures 8-11 

 Genotype, by designation, Valvulina youngi H. B. Brady 

 Valvulinella Schubert, Verb. k. k. Geol. Reicbs., 1907, p. 211. 

 Valvulina (part) of autbors (not Parker and Jones). 



Test conical, similar to Tetrataxis in general form, the interior 

 labyrinthic, two horizontal series of chamberlets developed in 

 each chamber, the divisions appearing through the thin outer 

 coating; aperture not cribrate. 



Carboniferous. 



Genus ORBITOLINA d'Orbigny, 1847 

 Plate 23, figures 12, 13 



Genotype, by designation, Orhitolina gigantea d'Orbigny 

 Orbitolina d'Orbigny, Prodr. Pal., vol. 2, 1850, p. 143. 



Test depressed, conical, lower side usually concave ; outer por- 

 tion of each chamber subdivided by secondary partitions; wall 

 of agglutinated siliceous particles; aperture in the adult con- 

 sisting of numerous pores on the basal side. 



Cretaceous. 



Genus DICTYOCONUS Blanckenhorn, 1900 



Plate 23, figure 14 



Genoholotype, Patellina aegyptiensis Chapman 



Dictyocoyius Blanckenhorn, Zeitschr. Deutsch. Geol. Ges., vol. 52, 1900, 

 p. 433. 



Test conical; chambers annular and divided into chamberlets, 

 central portion, a mass of chambers in layers parallel to the base 

 of the test, without pillars; wall finely arenaceous, calcareous 

 with a fine exterior layer, below which is a sub-epidermic, finely 

 reticulate structure, exposed in worn specimens. 



Eocene. 



Genus CUSHMANIA Silvestri, 1926 



Plate 23, figure 16 

 Genoholotype, Conulites americana Cushman 



Cushmania Silvestri, Mem. Pont. Accad. Sci. Nuovi Lincei, vol. 9, 1926, 

 p. 7. 



