152 PALEONTOLOGY OF NEW JERSEY. 
Formation and locality: In the dark micaceous clays beneath the Lower 
Green Marls at Haddonfield, New Jersey. Collection Acad. Nat. Sei. 
Phila., where it was found in the tray with Leiostrica cretacea Conrad. 
LITTORINIDZ. 
Genus MODULUS Gmelin. 
MODULUS LAPIDOSA, nN. sp. 
Plate xvu, Figs. 6-8. 
Delphinula ? lapidosa (Mort.) Meek, Check List Cret. and Jur. Foss., p. 18; Geol. 
N. J., Newark, 1868, p. 728. 
Straparolus lapidosus Gabb (in part): Jour. Acad, Nat. Sci., Phila., vol. 4, 2d ser., 
p. 300, Pl. xtvin, Fig. 5; but not of Synopsis and subsequent publications. 
Not Delphinula lapidosa Morton: Synop. Org. Rem. Cret., p. 46, Pl. x1x, Fig. 7, 
and Gabb’s Synopsis, p. 48. 
Shell rather small, subdiscoid above, with a flattened or but slightly 
convex spire, as seen in the internal casts, and a broadly rounded outer 
margin to the volutions and very shallow base. Volutions three or more, 
rather rapidly increasing in size, the last one slightly spreading at the aper- 
ture. Sutures very distinct. Umbilicus moderately large and the margin 
sharply carinate; also showing a strong groove along the base on the inside, 
indicating the existence of quite a strong spiral ridge on the inside of the 
aperture of the shell just above the base. The aperture has been propor- 
tionally large, higher than, wide, obliquely subovate, rounded above and 
pointed at the base of the inner lip, with the spiral ridge as above described 
just above the base; surface unknown. 
The casts of this species have the features of the genus Delphinula, with 
the additional one of the tooth-like ridge on the columellar lip a little above 
its base. In this feature it agrees most nearly with the characters of the 
genus Modulus Gmelin, and none of the other features yet known to belong 
to it would disagree with those of that genus. I have before me casts of 
four individuals more or less imperfect, but all showing in a satisfactory man- 
ner the groove left by this tooth-like ridge and the angular base of the 
aperture. For this reason I conclude to place this species under the genus 
