374 CRETACEOUS PALEONTOLOGY. 



1864. Nuculana pinnaformis. Meek, Check List Inv. Foss. N. 



A., Cret. and Jur., p. 8. 



1868. Nuculana pinnaformis Con., Cook's Geol. N. J., p. 725. 

 1886. Nuculana pinnaformis Whitf., Pal. N. J., vol. i (Monog. 



U. S. G. S., vol. 9), p. 108, pi. n, figs. 7-8. 

 1905. Leda pinnaforme Johns., Proc. Acad. Nat. Sci. Phil. 



(1905), p. 8. 



Description. Shell small, the dimensions of the type speci- 

 men being: length, 6.5; height, 4.7 mm.; cimeate-subovate in 

 outline, the anterior margin rather broadly rounded, the ventral 

 margin rather strongly convex in the middle, the posterior ex- 

 tremity pointed; valves strongly ventricose in the middle, be- 

 coming compressed posteriorly. Beaks large and rather promi- 

 nent, situated about two-fifths of the length of the shell from the 

 anterior extremity; along the postero-cardinal margin the edge 

 of the shell is inflected to form a narrow, nearly linear area ex- 

 tending from the beak to the posterior extremity. Surface of the 

 shell marked by conspicuous, regularly concentric lines which 

 become obsolete at the margin of the linear area along the post- 

 cardinal margin. Characters of the hinge-line not observed. 



Remarks. No examples of this shell have been met with in 

 the recent collections of the Survey, and the species is apparently 

 represented by the single individual upon which it was founded. 

 Whitfield illustrated a second specimen and referred it to this 

 species, but this identification is probably incorrect, and the speci- 

 men perhaps belongs to the species L. marlboroensis, described 

 for the first time in the present report. L. pinnaformis may 

 be recognized, should it be met with in future collections, by its 

 short, ventricose form, and its strong, concentric, markings. 



Formation and locality. Woodbury clay, Haddonfield (183). 



Geographic distribution. New Jersey. 



Leda marlboroensis n. sp. 

 Plate XXIX., Figs. 18-23. 



Description. Shell small, the dimesions of a small internal 

 cast being: length, 6 mm.; height, 3.5 mm.; convexity, 1.5 mm. 

 The dimensions of a larger individual are: length, 13.5 mm.; 



