234 NEW YORK STATE MUSEUM 



plications are crossed by fine concentric lines. Length and hight of 

 typical specimen, 19 mm. 



This species resembles in general aspect, L. ornatum, but the latter 

 at a hight of 19 mm has from 46 to 50 plications which are fiat topped, not 

 rounded as in L. a ceo la. The subcircular outline of L. accola is also 

 quite characteristic. The species is based on rather meager material which 

 represents the only evidence of the true Pinnopsis type found in the 

 western subprovince, excepting L. wiscoyense from the upper Genesee 

 valley. 



Habitat. Genesee province ; Chautauqua subprovince. Ravine at 

 West Falls, Erie co., not far below the horizon of the Portage sandstone. 



Lunulicardium (Chaenocardiola) clymeniae sp. now 



Plate 2, fig. 1-6 



Shell of medium size, subpyriform in outline with nearly vertical 

 anterior margin, the sical margin extending for the greatest diameter of 

 the valves. Beak moderately prominent, incurved at the apex, which is 

 directed toward the postlateral margin [see description and illustration of 

 the beak on p. 224]. Beneath the beak lies the triangular cardinal area, 

 below which are a few coarse, angular, interlocking plications. The 

 margin has a strongly convex curvature outward from this point to the 

 lower margin, where it is somewhat transverse. The anterior margin is 

 straight, passing from the beak to the base axially or just before the axis; 

 in contrast to the thin edges elsewhere on the valve, the shell is here 

 greatly thickened. The sicae are broad, flat and vertical, broadest on 

 the umbonal region, tapering outward at first abruptly, thence more gently, 

 and ending somewhat obtusely at the margin. The hiatus is elongate 

 cordiform. 



The surface slopes pretty regularly from the sical margins, there being 

 a slight concavity sometimes apparent close to the sical margin near the 

 lower edge of the shell. 



The surface sculpture consists of exceedingly fine radial filiform lines 

 six in the space of 1 mm over the middle of the valve. These are increased 



