18 PEOCEEDINGS OF THE liTATIOlSrAL MUSEUM vol.72 



are slightly raised, forming a sort of pseudo-laterals. The 

 anterior raised margins are separated from the anterior cardinals 

 by pronounced channels. The resilifer is broad and subtrigonal, 

 and at its lower margin just back of the posterior cardinal 

 on each valve is a small pit. On the left valve on the posterior 

 side of the resilifer close to the margin, is a narrow ridge or pseudo- 

 cardinal. Some distance back of the resilifer near the inner margin 

 is a very low broad hump suggesting a rudimentary lateral, and 

 between this and the slightly raised outer margin above is a shallow 

 channel. A similar hump occurs near the inner margin a short 

 distance in front of the socket on the right valve. Lunule distinct 

 and deep, most sharply outlined on the left, valve. Escutcheon dis- 

 tinct, but shallow, sharply defined on the right valve, less so on 

 the left valve. 



Adductor scars subequal strongly impressed; back of the upper 

 end of the anterior scar is a small deeply impressed retractor scar. 

 Pallial line simple. Most of the internal casts show a depression,' 

 corresponding to an internal ridge, beginning just in front of the 

 beak, extending in a broad regular curve downward and backward, 

 and dying out before reaching the pallial line. Inner margin of 

 the shell finely crenulated. 



The dorsal margins of the shell slope from the beak at an angle 

 of about 130° ; the antero-dorsal margin rounds down into the regu- 

 larly but rather sharply rounded anterior margin, and this in turn 

 into the broadly and regularly rounded ventral margin; posterior 

 margin subangular below, slightly truncated above. 



Surface marked by rather coarse growth lines of irregular strength. 



Re'inarhs. — Internal casts of this species were figured without spe- 

 cific name in North Carolina Geological and Economic Survey.* 

 The new material includes one nearly perfect left and one nearly 

 perfect right valve, several imperfect right and left valves, and 

 several internal calcareous sandstone casts, one of which is nearly 

 perfect on the right side. 



The specimens figured by Weller^*^ in his Plate 41, figures 1 and 

 2, under the name GrassatellUes suhplanus (Conrad), appear to be 

 very close to this species, but they are relatively shorter. The speci- 

 mens are, however, relatively longer than Conrad's type of C. sub- 

 'planus and I question the correctness of their identification. 



The species Crassatellites vadosus (Morton) which is very common 

 in the upper part of the Ripley formation of the Gulf Coastal Plain 

 in beds which are of about the same age as the Cretaceous stratum 

 uncovered in the Rocky Point quarries, is more convex and more 



9 Vol. 5, p. 277, pi. 68, figs. 5-7, 1923. 



1" Weller, Stuart, A report on the Cretaceous Paleontology of New Jersey, Geol. Survey 

 New Jersey, Paleontology, vol. 4, p. 553, pi. 41, figs. 1, 2, 1907. 



