MOLLUSCA. 629 



project above the general line of the hinge. Hinge slightly con- 

 cave posterior to the beaks, and the margin considerably thick- 

 ened, as indicated by the form of the cast. Anterior to the beaks 

 the cardinal line declines at a low angle from the direction of the 

 posterior side. Basal line very strongly curved; extremities 

 rounded, the anterior the most sharply so. Anterior muscular 

 scar moderately large, triangularly ovate, bordered by a rounded 

 furrow on the posterior side, indicating a slightly thickened rib 

 on the interior of the shell. Posterior scar larger, triangular, and 

 faintly marked. Pajlial sinus deep and extending to near the 

 middle of the shell's length. Hinge features unknown. Indica- 

 tions exist on the cast of a divided tooth-like projection on the left 

 valve, with a socket-like plate on the right." (Whitfield). 



Remarks. This species has not been met with in the recent 

 collections of the Survey, and the type specimen described by 

 Cabb seems to be the only example which has ever been recog- 

 nized. In Whitfield's illustration of this type specimen, the fur- 

 row behind the anterior muscular scar is represented somewhat 

 deeper than it actually is upon the specimen. 



Formation and locality. Navesink marl, Burlington county 

 (Gabb). 



Geographic distribution. New Jersey. 



Genus SOLYMA Conrad. 



Solyma lineolata Conrad. 

 Plate LXXL, Figs. 3-6. 



1870. Solyma lineolatus Con., Am. Jour. Conch., col. 6, p. 75, 



fig. 9. 

 1876. Solyma lineolatus Gabb, Proc. Acad. Nat. Sci. Phil. 



(1876), p. 305. 

 1884. Solyma lineolatus Tryon, Struct, and Syst. Conch., vol. 



3, p. 134, pi. 105, fig. 89. 

 1886. Solyma lineolata Whitf., Pal. N. J., vol. i (Monog. U. 



S. G. S., vol. 9), p. 182, pi. 25, figs. 11-13. 

 1905. Solymya lineolata Johns., Proc. Acad. Nat. Sci. Phil. 



(1905), p. 17. 



