EARLY UE\OXIC HISTORY OF XEVV YORK AND EASTERN NORTH AMERICA 213 



Pholidops terminalis Hall 



P h o 1 i d o p s terminalis Hall. Palaeontology of New York. 1859. 3:490, pi. 



103B, fig. 8a-d 

 Pholidops a r e n a r i a Hall. lilem. 1867. 4: 413, pi. 3, fig. 24 

 Ph o 1 i d o J) s t c r ni i n a 1 i s Clarke. N. Y. State Mus. Mem. 3. 1900. ]). 59, pi. 8, 



fig- 23-25 



This relatively large species, characterized by its circular marginal 

 outline, and projacent apex, is rare in the Gaspe limestone, though very 

 common in the Oriskany of eastern New York and of Maryland. 



Localities. Shore outcrops at Grande Greve and at Perce Rock. 



Orbiculoidea mentis nov. 



Plate 47, figures 21-24 



Shell very large, brachial valve highly elevated, suberect, much larger 

 on the posterior than on the anterior slope. Posterior curvature concave 

 beneath the arched beak ; in front of the beak the surface is convex, the 

 shell being uniformly expanded in the pallial region. Marginal outline 

 subcircular. Surface bearing fine distant elevated concentric striae which 

 may undulate and inosculate. These are crossed by very fine radial lines 

 which probably do not pertain to the epidermal layer. 



The pedicle valve is concave exteriorly though the beak is elevated and 

 the pedicle slit does not extend to the margin. 



Dimensions. One brachial valve, virtually uncompressed, has a 

 diameter of 57 mm and its original hight was about 35 mm. Another 

 which has undergone compression apparently had a diameter of about 

 65 mm. A pedicle valve has a diameter of 45 mm. 



Localities. At Grande Greve and in the Perce Rock. 



Species name. The Sieur de Monts, explorer of New France, 1603. 



Orbiculoidea sp. ? 



Plate 47, figures 19, 20 



A species of moderately large size with suborbicular outline, regularly 

 concentric surface markings and not highly elevated brachial valve occurs 

 occasionally and resembles a shell found in the Glenerie Oriskany and not 

 very unlike O. jervisensis Barrett from the Port Ewen beds of Orange 

 CO., N. Y. 



Locality. Shiphead, 300 feet below the lighthouse. 



