150 PALEONTOLOGY OF NEW JERSEY. 
EULIMIDZK. 
Genus LEIOSTRACA H. and A. Adams. 
LEIOSTRACA CRETACEA. 
Plate x1x, Figs. 2-5. 
Eulima cretacea Conrad: Am. Jour. Conch., vol. 5, p. 100, Pl. rx, Fig. 15. 
Shell small, slender, subulate, spire very much elevated, smooth and 
polished; volutions nine or more (eleven, Conrad), flattened between the 
sutures, the upper edge of any volution slightly smaller than the lower edge 
of the one immediately above it, making the sutures remarkably distinct 
for a shell of this group; body volution rounded subangular in the lower 
part and rather rapidly contracted below to the short columella; aperture 
ovate-elliptical, acute above and rounded below; outer lip thin and sharp, 
inner lip smooth, without callus or ridges; surface polished, entirely desti- 
tute of lines or other markings. On one individual, on which the lip is broken 
away for one-third of the volution, there occurs a distinct spiral ridge above 
the columella proper and just below the junction of the outer lip with the 
body of the volution, within the aperture. 
This small but beautiful shell presents the general appearance of the 
genus Hulima Risso., except that the spire is straight, and there are no evi- 
dences of the periodic mouths common to that genus. In the form of the 
aperture it more closely resembles Leiostraca, but the volutions are more 
decidedly flattened externally between the sutures. It seems to be more 
nearly related to this latter genus than to any other established one. But 
if the ridge found within the aperture of one of the individuals should 
prove to be a constant feature, it would deserve a separate generic name. 
This ridge, cccurring as it does just below the top of the aperture on the 
inner side, is peculiar, and may possibly be an accidental feature of the 
individual; but I can not verify it without destroying the borrowed speci- 
men. Mr. Conrad remarks under his description of the species that it is 
‘distinguished by the whorls of the spire suddenly curving inward above 
the suture.” This feature arises from the fact that the coiling of the volu- 
tion is just below the swell of the one above, but is seen distinctly only on 
