AND AYES OF NOKTII AMERICA. 



147 



Depth within (distally), 

 Greatest width, 

 Width at emargination, 



Lines. 



7. 

 16.5 



13.5 



A costal bone of I lie right side, with its external portion broken away, accompanied the above, but probably does 

 noli belong to the same speoies. It is thin, and the head of the rib is almost cylindrio. The surface is marked with 

 delicate vascular grooves, which are largely parallel to each other. The external angle of a vertebral scute falls near 

 the posterior border 2.3 inches from the vertebral suture, indicating considerable breadth. The angle is right. Th e 

 anterior outer suture is slightly concave, and begins to assume a nearly longitudinal direction on the costal suture, 

 one inch from the vertebral. 



Width of bono, 

 Thickness at lateral suture, 

 Longer vertebral suture, 



Lines. 

 23.5 

 2.5 

 14 



The specimen indicating this speoies was found near Pemberton, Burlington Co., N. J., and was presented to the 

 Museum of the Academy by Dr. Samuel ^shhurst. At the same time and place were found plates and a broken femur 

 of correlative size of a large individual of Prochonias sulcal us; the latter measured 18 linos across head, and 1G across 

 condyles. There were also remains of Adocus, Kyposaurus, Holops, and Mosasaurus. 



Prof. Leidy describes (Cretaceous Reptiles) two species of Marine Turtles Chelone sopita, and Chelone ornata. 

 There is no evidence that the mandible herein described pertained to either of these species, and the identification of 

 the accompanying marginal bones indicates a considerable difference. These are in the present species concave be 



low, iu the P. sopita convex or plane. In L. angusta the suture of the dermal scutes marks ail entrant angle; in the 

 P. sopita, a projecting one. The same bones are relatively narrower than in any of the species of Osteopygis, and 

 have planer margins, and round pits. Their narrowness suggests that the oxtremital marginals may have been still 



loss united with the disc than in the species of Proploura. 



Tins species is also known from the three marginal bones, and part of a fourth, described and figured by Dr. 

 Leidy, as above. I suppose them to be from the sixth to the ninth of the left side, inclusive. The animal has suffered 



an injury, as a deep notch is cut in the margin between the eighth and ninth, and another just behind the rib-pit of 



the ninth. 

 The species differs markedly from the P. sopita in the flatness and slenderness of the more lateral marginal bones, 



and were it not for the posterior marginal of the P. angusta preserved, might be referred to that tortoise. The inner 



edge of the seventh is not so deep as in the P. sopita, and the breadth relatively less; the same is true of the sixth. 



The superior edge is prolonged but little beyond the inferior. The pits for the costal pegs are behind the line of the 



posterior two-fifths of the length, on all the bones. Pits round conic, inner edges equal. Margin from seventh slightly 



curved up. 



Lines. 



Width sixth, 18 



Depth " on inner border, 10.5 



" seventh " " '.) 



Length " " " 31.5 



Width. " (average, £0.5 

 Width of eighth, J the length. 



Prom the upper Cretaceous Green Sand Bed, Mullica Hill, Gloucester Co., N. J. 



EUCLASTES. 



Cope, Proceedings Academy Nat. Sciences, 1867, p. 39. 



