224 PALEONTOLOGY OF NEW JEESEY. 



Genus GEYPHEA Lam. 



Gryphaea vesicularis Lam. 



Plate XXIX, Figs. 7 and 8. 



For references and synonyms see page 36. 



It is generally supjiosed that the genus Gryphsea does not occur in beds 

 above the true Cretaceous, hence I have hesitated somewhat before referring 

 the single specimen of an internal cast figured on Plate 39, Figs. 7 and 8, to 

 G. vesicularis Lam. But on critical examination I can find no reason to 

 doubt the truth of the reference. The form and character of the specimen 

 are pi'ecisely those which would be given by the internal cast of one of the 

 small variety of the species as they occur in the marls of the middle beds, 

 with the exception of the more marked extension of the siphon-like protu- 

 berance on the side, in which respect it corresponds more closely to the form 

 of the larger individuals from the Lower Marls. The muscular scar on the 

 specimen is well mai-ked, and all the features are those of an old and much- 

 thickened shell in which the rostral cavity has become filled by excess of 

 thickening; and I can see no reason whatever for not considering it as iden- 

 tical generically and specifically with the shells from the Cretaceous marls 

 below. There can be no question as to the authenticity of its locality and 

 position, as, fortunately, the specimen bears on the under surface an im- 

 print of Cardita j^erantiqua Con., which at once fixes the position beyond 

 question. It is possible that this may be a Cretaceous specimen broken 

 from its original bed and redeposited in the Eocene seas. If so, however, 

 it' is the only case yet known in the State. 



The example is from the upper layer of the Uj^per Marl at Shark 

 River, New Jersey. 



PECTENIDiE. 



Genus PECTEN Klein, 

 Pecten Kiieiskemi. 

 Plate XXIX, Figs. 3-5. 

 Pecten KneisJcerni Coni-ad. Am. Jour. Couch., Vol. V, p. 40. 



Mr. Conrad's description of this shell is as follows: "Ovate, convex, 

 ribs i;^, convex, little prominent; anterior and posterior submargins with- 

 out ribs; ears equal. (Cast.)" 



