FAMILY 11. VALVULINIDAE 129 



arenaceous, usually fairly smooth and with much cement; aper- 

 ture at the inner margin of the chamber with a simple valvular 

 tooth. 



Carboniferous to Recent. 



Genus ARENOBULIMINA Cushman, 1927 

 Plate 12, figure 17; plate 13, figure 21 



Genoholotype, Biilimina presli Reuss 



Arenohulimma Cushman, Contr. Cushman Lab. Foram. Res., vol. 2, 1927, 



p. 80. 

 BuUmina (part) Reuss, Verstein. Bohm. Kreide, 1845-46, pt. 1, p. 38, 



(and later authors). 



Test with the earlier chambers triserial, the angles rounded, 

 later chambers spirally arranged with many chambers to a 

 whorl, close coiled ; wall finely arenaceous usually with a large 

 proportion of cement and smoothly finished ; aperture with a 

 broad rounded tooth. 



Cretaceous. 



Genus ATAXOPHRAGMIUM Reuss, 1861 

 Plate 12, figures 18-20 



Genotype, by designation, Bulimina variabilis d'Orbigny 



Ataxophragmium Reuss, Verz. Gypsmodellen Foraminiferen, (1861) 



nos. 8, 9. 

 Bulimina (part) d'Orbigny, Mem. Soc. Geol. France, ser. 1, vol. 4, 1840, 



p. 40, (and later authors). 



Test in the very early portion triserial, later with a spreading 

 coil of several chambers; wall arenaceous with much cement; 

 aperture extending in from the edge in young until in the adult 

 it may become enclosed in the apertural face. 



Cretaceous. 



Genus CRIBROBULIMINA Cushman, 1927 

 Plate 12, figures 21, 22; plate 13, figure 22 



Genoholotype, Valvulina mixta Parker and Jones 



Cribrobulimina Cushman, Contr. Cushman Lab. Foram. Res., vol. 2, 



1927, p. 80. 

 Valvulina (part) Parker and Jones, in Carpenter, Parker and Jones, 



Introd. Foram., 1862, p. 146. 



