40 PALEONTOLOGY OF NEW JERSEY. 



ber and increase very rapidly in size, with wide sutures in the cast, indi- 

 cating a thickened shell ; aperture large, semilunate above, but contracted 

 below to fonn the canal ; the columellar cavity in the cast rather large, 

 without any evidence of fold or twisting; surface of the casts usually 

 smooth, the markings of the shell not transmitted to its inner surface, but 

 often marked on the inner face of the whorls; the shell as shown on two 

 different indi^•iduals, one preserving a portion of the substance, the other 

 retaining a part of the matrix, has been covered by very strong, nodose 

 spiral bands or ridges, with sometimes smaller secondary lines between. 

 These have even existed on the columella and the beak, and very closely 

 resemble the markings of P. trochifonnis, from which it differs, however, 

 in the flattened iipper surface of that species and the strong fold on its 

 columella. 



Formation and locality : In the Lower jSrreen Marls at Freehold and 

 Crosswicks Creek and at the Neversink Hills, New Jersey, and in iron 

 nodules from the plastic clays near Freeport, New Jersey. Collections at 

 Rutgers College. 



PyROPSIS ? OBESA, 11. Sp. 



Plate III, Figs. 13, 1.3. 



Shell of moderate size, very veutricose, with very round, full, short 

 volutions, and short obtuse spire, the body volution being produced below 

 to form a short beak of almost insignificant proportions, as shown by the 

 cast; apical angle about 80 degrees; volutions about three in number, very 

 short and compact; smooth on the surface, except on the last one, where 

 spiral lines are shown to have existed on the shell and to have left their 

 imprint; only about five or six of these traceable, and those on the lower 

 side ; aperture moderately large, obliquely ovate, rounded above and pointed 

 below; columella rather strong, somewhat flexuose, judging from the axial 

 cavity left in the cast, and apparently marked by a single, rather promi- 

 nent oblique ridge in its lower part. 



This cast presents the general features of a Pi/ropsis, but differs in the 

 possession of the columellar fold or ridge, and I am at a loss to place it sat- 

 isfactorily under any known genus. Perhaps the matrix might show its 



