OF DENISON UNIVERSITY. 8$ 



ular concentric striae. Length 14 mm; height 9.5 mm; thickness 8.5 

 mm ; beaks 4 mm. from front. 



This species was collected by W. F. Cooper, in the nodules and 

 shale at the lowest exposure at Moot's run, 4 miles west of Granville. 

 Although suggesting the genus Palaeoneilo strongly we do not see how 

 the hinge characters here described can permit this species to fall into 

 anv known genus. 



Pholadella neichernji, H- and \V. 

 (Plate III, Fig. 27; Plate IV, Fig. 4.) 



Shell large, elongated, rather flat, more than twice as long as high, 

 very short anteriorly, produced and rather narrow posteriorly. The 

 lower margin is nearly straight, being rather abruptly curved anterior- 

 ly and more gradually posteriorly where it is produced to form an 

 acute angle ; posterior margin oblique, forming with the upper a very 

 large angle; hing-line concave, shorter than the length of shell; the 

 anterior margin short, nearly straight; umbones very prominent, beaks 

 incurved over the hinge-line; post-umbonal ridge quite prominent, 

 curved and becoming less distinct to its intersection with the lower 

 posterior angle ; post-umbonal slope quite abrupt near the beak, but 

 becoming less so posteriorly ; anterior to this ridge the surface is 

 marked by numerous radiating thread-like strice, which seem almost to 

 lie upon rather than to form a part of the shell ; these striae ah 

 rupily cease at a point on the lower margin one-fifth the length 

 from the anterior ; shell otherwise covered by strong concentric lines 

 and folds of growth. Prominent characters are the prominent and el- 

 evated umbones with the concave hinge line, oblicjue posterior mirmn 

 and radiating striae. 



Length 90 mm; height at beak 35 mm ; height posteriorly 30 

 mm; beak distant from anterior margin 13 mm. 



Our specimens are apparently little distorted and are much ( ' .;) 

 larger than those figured by Meek from Rushville. There ran be um 

 doubt of the identity, but our specimens show Meek's types to haw 

 been much more distorted than Meek's P. (Sedgwickia ?) obliqua pro- 

 posed for the fragment figured. The species is apparently restricted 

 to a rather narrow zone below the shale immediately underlying congl. 



