MOLLUSCA. 609 



irregular, concentric lines of growth only. Hinge of the left 

 valve with three cardinal teeth diverging from beneath the beak,, 

 the two anterior ones of about equal length, extending directly 

 beneath the beak with a triangular pit between them, the pos- 

 terior one much more oblique and more elongate. In front of 

 the cardinal teeth is a single low lateral beneath the lunule and 

 parallel with the shell margin. In the right valve there are two 

 divergent, bifid cardinal teeth with a pit beneath the lunule for 

 the reception of the anterior lateral tooth of the opposite valve. 



Remarks. This species occurs somewhat commonly in the 

 Marshalltown clay-marl near Swedesboro with the shell substance 

 preserved. These specimens have been compared with the types 

 of the species and their identification is certainly correct. The 

 species is much like M. tippana. It attains but little more than 

 one-half the size of that species, however, and the hinge-teeth are 

 different, the bifid anterior cardinal tooth of the right valve (not 

 the left valve as stated by Conrad) being quite different from 

 the same tooth in M. tippana. The species is a member of the 

 family Veneridae rather than Tellinidae, and there seems to be no 

 essential reason for recognizing Mora as a genus distinct from 

 Meretrix. 



Formation and locality. Woodbury clay, near Haddonfield 

 (183) ; Marshalltown clay-marl, near Swedesboro (177). 



Geographic distribution. New Jersey. 



Meretrix eufaulensis (Conrad). 



( 

 Plate LXVIIL, Figs. 8-10. 



1860. Callista Eufaulensis Con., Jour. Acad. Nat. Sci. Phil., 2nd 



ser., vol. 4, p. 282, pi. 46, fig. 24. 



1861. Callista Enfalensis Gabb, Synop. Moll. Cret. Form., p. 



161 (105). 

 1864. Dione eitfalensis Meek, Check List Inv. Foss. N. A., Cret. 



and Jur., p. 13. 

 1886. Callista delawarensis Whitf., Pal. N. J., vol i (Monog. 



U. S. G. S., vol. 9), p. 153, pi. 22, fig. 10 (not figs. 



8-9). 



39 PAI, 



