LAMELLIBRANCEIATA FEOM BASE OF UPPER MARLS. 217 



of the shell. The anterior scar is not distinctly marked, and its limits are 

 not well defined. Pallial line distinct, the sinus very deep and rounded at 

 the end, which is projected in the direction of the axis of the shell. 



Formation and locality, — In the lower part of the Upper Marls, near 

 New Egypt, New Jersey. In the collection at Rutgers College. 



MACTRID^. 



Genus YELEDA Conrad. 1871. 

 (Am. Jour. Concli., Yol. YI, p. 74.) 



Veleda nasuta, n. sp. 

 Plate XXVIII, Fig. 23. 



Shell of medium size, transverse, about twice as long as high, and 

 moderately convex. Beaks small, appressed, rising but a little above the 

 hinge line, and situated very nearly in the middle of the length of the shell 

 Cardinal line arched, and declining almost equally on each side of the beak, 

 the posterior side, if either, being the most abrupt and less arcuate, the 

 angle formed by the opposite sides being about 135^; basal line less arched 

 than the dorsal, and a little the most ventricose opposite the beaks, while it 

 becomes almost straightened near the posterior extremity. Anterior end of 

 the shell sharply rounded, but a little wider than the posterior, which is 

 narrow and vertically truncate on the margin. Disk of the valves most 

 ventricose on the umbones and along the anterior slope, where it is abruptly 

 rounded. Posterior umbonal ridge slightly angular, and the posterior car- 

 dinal slope narrow and abrupt. Surface of the shell only partially pre- 

 served, but so far as it exists is seen to be marked bv fine irreg-ular lines of 

 growth, with a few stronger undulations of the surface. Interior unknown. 

 Shell substance verv thin and fraorile. 



This species closely resembles F. transversa Whitfield in general form, 

 but is not quite as high in proportion to the length ; it appears to have been 

 more ventricose, and lacks the even, regular, concentric lining of the surface. 



Formation and locality. — In the dark green marls at the base of the 

 Upijer Marls, near New Egypt, New Jersey. In the collections of the State 

 survey at Rutgers College, New Brunswick, New Jersey. 



