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GASTEROPODA OF THE LOWER GREEN MARLS. 45 
which the genus Pyropsis was originally founded, on account of the exist- 
ence of a ridge-like feature on the columella near the base of the aperture, 
which indicates a projection of the shell at this point and the oblique 
truncation of the anterior ends of the casts, features which would appear 
to ally this and the following species with Rapa papyracea Lam., and | 
strongly suspect that is where they both belong. 
Formation and locality: In the Lower Marls of New Jersey, at Mullica 
Hill and Holmdel. The specimens are invariably in a very poor state of 
preservation. 
Pyropsis (RAPA?) CORRINA, n. sp. 
Plate n1, Figs. 1-3. 
Shell of medium size, turbinate, with a nearly flat spire, consisting of 
two and a half to three volutions, and with a short base; volutions rounded 
above, and separated by deep, wide sutures in the casts, increasing very 
rapidly with the increased growth of the shell, broadly rounded on the 
periphery and angulated at the base, with a projecting border around the 
extremely wide and open umbilical cavity of the cast; aperture large, 
obliquely subovate, rounded above and on the outer side, straightened or 
strongly modified on the inner margin and pointed below; columella strong, 
or else hollow and formed by a free inner lip like that of Rapa; marked 
on the lower part by a strong angulation, which has projected into the 
aperture like a knee a short distance above the base; surface of the cast 
smooth, showing no evidence of spiral or transverse lines or ridges. 
I at first included this species among those referred to Pyropsis trachy- 
Jormis Tuomey, but was compelled subsequently to change its position from 
the evidence afforded by the knee-like projecting ridge of the columella, 
which I think allies this shell, and also P. septemlirata Gabb, with Rapa, 
deeming them closely allied to shells like R. papyracea Lam.; but from want 
of sufficient evidence I leave them in their present place doubtfully. 
Formation and locality: In the Lower Green Marls at Holmdel, New 
Jersey. From Prof. Reiley’s collection. 
