250 CRETACEOUS PALEONTOLOGY. 



: Polymorphina gibba (d'Orbigny). 



Plate III., Pig. 21. 



1826. Glohulina gibba d'Orbigny, Ann. Sci. Nat., vol. vii, p. 266 



No. 20; Modele No. 63. 

 1870. Polymorphina gibba Brady, Parker and Jones, Trans 



Linn. Soc. London, vol. xxvii, p. 216, pi. xxxix, fig 



2 a-d. 

 1884. Polymorphina gibba Brady, Chal. Rep., vol. 9, p. 561 



pi. 71, fig. 12. 

 1898. Polymorphina gibba Bagg, Bull. U. S. G. S., No. 88 



p. 61. 

 1898. Polymorphina gibba Bagg, Bull. Am. Pal., vol. 2, No. 10 



P- 30 (324)- 

 1901. Polymorphina gibba Bagg, Md. Geol. Surv., Eocene, p 



248, pi. 63, fig. 12. 

 1904. Polymorphina gibba Bagg, Md. Geol. Surv., Miocene, p, 



477, Pl- 133, %■ 4- 



Description. — "Test subglobular, apex slightly produced, base 

 obtusely rounded ; consisting of from two to four chambers, com- 

 pactly joined and overlapping; surface smooth, unmarked by 

 septal constrictions; septa visible as delicate, oblique lines, later- 

 ally very slightly compressed, though usually nearly circular in 

 transverse section; shell larger than Polymorphina lactea, less 

 elongated toward the apex; aperture mammillate. 



"Diameter, 0.5-1. 17 mm." (Bagg.) 



Formation and locality. — ^Navesink marl. Freehold (Bagg) ; 

 Vincentown limesand, Vincentown (Bagg). 



Geographic distribution. — New Jersey; Eocene of Maryland 

 and Virginia, Miocene of Maryland. 



Polymorphina lactea (Walker and Jacob). 

 Plate III., Figs. 22-23. 



1798. Serpula lactea Walker and Jacob (fide Kanmacher) ; 



Adams's Essays, second ed., p. 634, pi. xxiv, fig. 4. 

 1858. Polymorphina lactea Williamson, Recent Foram. Gt. 



Brit., p. 71, pi. 6, fig. 147. 



