572 CRETACEOUS PALEONTOLOGY. 



the beak, and another obscure one directed obliquely backward, 

 in front of the beaks is a single lateral tooth beneath the lunule 

 and close to the shell margin, back of the beak and remote from 

 it, extending nearly to the posterior extremity of the hinge-line, 

 is a low, elongate, posterior cardinal tooth. 



Formation and locality. Marshalltown clay-marl, near 

 Swedesboro (177). 



Geographic distribution. New Jersey, Mississippi. 



Family DIPLODONTIDAE. 



Genus TENEA Conrad. 



Tenea parilis Conrad. 



Plate LXIIL, Figs. 1-6. 



1860. Mysia (Diplodonta) parilis Con., Jour. Acad. Nat. Sci. 



Phil., 2d ser., vol. 4, p. 278, pi. 46, fig. 16. 

 1870. Tenea parilis Con., Am. Jour. Conch., vol. 6, p. 73, pi. 3, 



fig. 12. 

 1875. Tenea parilis Con., Kerr's Geol. N. Car., App. p. 8, pi. 



2, fig. 25. 

 1884. Tenea parilis Tryon, Syst. and Struct. Conch., vol. 3, p. 



216, pi. 119, fig. 72. 

 1886. Dosinia Gabbi Whitf., Pal. N. J., vol. i (Monog. U. S. 



G. S., vol. 9), p. 161, pi. 22, figs. 4-5. 

 1886. Tenea pmguis Whitf., Pal. N. J., vol. i (Monog. U. S. 



G. S., vol. 9), p. 163, pi. 22, figs. 1-2, not fig. 3 (not 



T. pinguis Con.). 

 1905. Tenea parilis Johns., Proc. Acad. Nat. Sci. Phil. (1905), 



P- IS- 



Description. Shell in large examples attaining a length and 

 height of 38 mm.; the depth of each valve being 13 mm. The 

 valves more or less strongly and evenly convex, subcircular, ob- 

 scurely subquadrangular or subovate in outline, beaks prominent, 

 directed forward, slightly incurved. The post-cardinal margin 

 deeply inflected. Each valve furnished with two cardinal teeth 



