TRANSACTIONS OF WAGNER 

 640 



TERTIARY FAUNA OF FLORIDA 



Miocene of North Carolina? Wagner; of York River, Virginia, station 

 2250, Harris; of Duplin County, North Carolina (young), Burns. 



Shell large, solid, squarish, moderately inflated, with subcentral, proso- 

 crelous, rather elevated beaks ; left valve with about thirty ribs, with subequal 

 interspaces, the anterior ribs squarish, with a shallow median sulcus near the 

 margin, and irregular concentric ripples ; the ribs of the middle of the valve 

 not sulcate, with less rippling, more closely adjacent, the interspaces very 

 squarely channelled ; the posterior ribs smaller, rounded, and more closely 

 set ; cardinal area short, rather wide, smooth, or longitudinally striate, with 

 three concentric lozenge-shaped groovings ; hinge-line short, solid ; the teeth 

 not interrupted, strong, about forty-five in'all, the anterior more vertical, the 

 middle teeth inclining towards the middle line of the area, the posterior teeth 

 distally, more oblique and longer ; margins of the shell strongly fluted. Lon. 

 56, alt. 55, diam. 43 mm. (type specimen). 



As this species seems never to have been described, the references in 

 Bronn being merely to Wagner's unpublished plates, I have given a diagnosis 

 from Professor Wagner's original type specimen, and refigured the interior of 

 the left valve. The shell is remarkable for its squarish form, which is rather 

 distantly approached by some specimens of A. idonca. It is singular that in 

 all the years which have elapsed since this shell was collected and figured by 

 Professor Wagner no one has recognized or described it. 



Scapharca (Scapharca) dodona n. s. 

 PLATE 31, FIGURKS i, 8, Sa. 



Oligocene marl of Oak Grove, Santa Rosa County, Florida ; Burns. 



Shell small, solid, inequilateral, inflated, and rounded in front, pointed and 

 attenuated behind; with mesially impressed, prosoccelous beaks; left valve 

 with thirty-six squarish radial ribs, each with a deep central groove longitu- 

 dinally, the portions on each side with a shallower longitudinal sulcus, so 

 that each rib, except in young shells, is composed of four threads set in two 

 pairs ; the ribs separated from each other by channelled interspaces about half 

 as wide as the ribs ; concentric sculpture of numerous rather close set, regu- 

 lar, blunt, elevated lines, which appear on the riblets as fine undulations ; beaks 

 at the anterior third ; cardinal area, with a raised margin, lozenge-shaped, 

 rather wide, slightly narrower behind the beaks, with about four rather wavy 

 sets of concentric grooves ; hinge-line short, solid, the teeth not interrupted, 

 larger distally, the most anterior tending to break up into granulations, about 



