GASTEROPODA OF THE LOWEE GREEN MARLS. 101 



under his original description do not agree with those of this species, his 

 shell being proportionally wider; but I can find no other one agreeing 

 more nearly with it, so leave it as a synonym, since he so considered it him- 

 self, and I have not been able to find his type ; he had probably compared 

 with Mr. Conrad's original at the time he so placed it. 



Formation and locality : In the Lower Green Marls at Mullica Hill, at 

 Holmdel, and Monmouth County, New Jersey. Mr. Conrad's specimen 

 was from Tippah County, Mississippi. 



TURBINOPSIS ANGULATA, n. Sp. 



Plate XII, Figs. 17, 18. 



Shell rather above the usual size, short conical, and rather obese in 

 general form, oblique as seen from the back ; composed of two and a half 

 or three volutions, which increase somewhat rapidly in size with increased 

 growth; apical angle about 70°; volutions ventricose, obliquely flattened 

 on the upper side and obtusely round-pointed below, with a quite distinct 

 angulation at the upper third, or just above the upper third of the length, 

 as seen on the last one, and a less distinct one below the middle, dividing 

 the body volution into three sections, of which the middle one is rather 

 broader than the others and imperceptibly flattened; above the body volu- 

 tion the whorls are marked by about eight vertical folds, or angulations rep- 

 resenting folds, which do not extend to the suture line on the cast, the only 

 condition in which it has been observed; aperture elongate ovate, largest 

 below; columellar cavity in the cast of medium size, marked at the base 

 by a distinct groove, indicating the presence of a tooth-like ridge on the 

 shell, showing the generic position of the species ; the surface has also been 

 marked by spiral lines or ridges, fifteen or more in number, on the last 

 whorl near the lip, very perceptible on the surface between the whorls in 

 the cast. 



This species differs from any of the associated forms, by the angula- 

 tions of the volutions, and in the pi'oportional size and form of the volutions 

 themselves. There is only a single authentically identified cast, and that 

 one imperfect in the upper part of the spire, but its features are so very 

 distinctive that it may readily be distinguished from any other species in 

 the green marls. 



