GASTEBOPODA OF THE LOWER GREEN MARLS. 103 



ridge; surface of the cast showing rather distant vertical folds, but very 

 little indication of spiral striae, the shell being probably too thick for them 

 to be transmitted to the cast. 



This species diflFers from T. Hilgardi, as identified from New Jersey, in 

 the more elevated spire, larger umbilical opening, more rounded volutions, 

 and more distant vertical folds; from T. plicata, herein described, in its 

 more ventricose form, less oblique volutions, larger umbilical opening, 

 absence of tooth, and more distant vertical folds. 



Formation and locality: In the Lower Green Marls at Crosswicks, New 

 Jersey. From the collection Acad. Nat. Sci., Phila. 



TURBINOPSIS MAJOR, n. Sp. 



Plate XII, Figs. 15, 16, 31-33. 



Shell very large as compared with other species of the genus, the frag- 

 ment of a cast figured measuring over 1| inches across the body volution, 

 while the entire height lias not been less than 2.^- inches; volutions large, 

 heavy and massive, strongly rounded on the surface, and probably about 

 five in number; spire short, the apical angle having been about 60°, making 

 the height of the spire above the top of the- body volution, when measured 

 on the back of the shell, about equal to the length of the body volution 

 from that point downward; aperture obliquely elliptical-ovate, as in other 

 species of the genus; columellar cavity in the cast veiy large, measuring 

 nearly half an inch in its greatest width, the lower edge lieing raised above 

 the general surface, indicating a notch or groove at the base of the aper- 

 ture in the shell, with a rounded callosity above it, forming or representing 

 the tooth or fold on the columella; siu-face of the shell, as shown on the 

 surface between the volutions, marked by distant spiral ridges, at least on 

 the lower sides of the volution, and also by much more distant vertical 

 ridges or folds. 



The species as represented by the fragments in hand is so distinct in 

 size and proportions from any of the others recognized that it can not be 

 confounded with them, while its general features are so marked that it will 

 be readily distinguished from any other shell found in New Jersey or else- 

 where. 



