6i6 CRETACEOUS PALEONTOLOGY. 



is deflected in the casts so as to form a rather narrow flattened 

 area extending from the beak in each direction and gradually 

 dying out before reaching the anterior and posterior extremities 

 of the shell; just beneath the beak this flattened area bears the 

 impressions of the hinge-teeth. Surface of the casts smooth, 

 except for a few very faint and indistinct radiating costa; just 

 above the postero-cardinal slope of the valves. Pallial sinus ver}; 

 deep, extending beyond the middle of the shell. Hinge-teeth 

 small and weak, situated just beneath the beak, a single one in 

 the left valve with a socket on either side, and two in the right 

 valve with a deep socket between. 



Remarks. — Besides several fragments, two good internal casts 

 of this species are present in the collection. The larger of these, 

 a left valve, has lost the anterior extremity of the shell, and the 

 smaller one, a right valve, is injured at its posterior extremitj'-. 

 Between the two, however, all the characters of the shell can be 

 seen. Because of the imperfection of the specimen, the longi- 

 tudinal dimension of the larger specimen, given above, is subject 

 to slight error, but the smaller one is complete enough for accu- 

 rate measurement. In the Wenonah sand near Marlboro several 

 fragments of a large Tellina-\ik& shell have been collected which 

 resemble this one, the largest of which must have been about 60 

 mm. in length when complete. These specimens from near Marl- 

 boro, however, although internal casts, have had the external 

 markings of the shell impressed upon them by the compression 

 of the soft imbedding material after the solution of the shell itself. 

 These markings are regular concentric lines from one-half to 

 one millimeter apart. It is not possible to determine whether pr 

 not the type of the species was marked in a similar manner. 

 These specimens have been compared with Gabb's types of the 

 species in the collection of the Philadelphia Academy of Sciences, 

 and there can be no question as to their specific identity. 



Formation and locality. — Wenonah sand, near Crawfords Cor- 

 Corner (126^), ? near Marlboro (130O. 



Geographic distribution. — New Jersey, Georgia. 



