146 PALEONTOLOGY OF NEW JERSEY. 
others with which it is associated in the New Jersey beds, in the flat- 
ened volutions and in the surface characters. In some of the casts the 
upper whorls are somewhat rounded from the greater amount of deposit 
on the inside of the older parts of the shell, but they never attain that 
degree of wide separation of the volutions, with wide sutures, that is 
common in Z. vertebroides; while even in the most thickened specimens 
the lower whorls show the rectangular form of the volutions, and usually 
retain some evidence of the spiral lines. The general aspect as furnished 
by these casts indicates a thin and rather delicate shell, instead of the 
thick, heavy shell of 7. vertebroides and T. encrinoides. 
Formation and locality: In the Lower Green Marls at Crosswicks 
Creek, near New Egypt; at Upper Freehold; Holmdel and Walntord, 
New Jersey. 
TURRITELLA VERTEBROIDES. 
Plate xvii, Figs. 13-18. 
Turritella vertebroides Morton: Synop. Org. Rem. Cret., p. 47, Pl. m1, Fig. 13 ; 
Gabb, Synopsis, p. 92; Meek, Check List Cret. and Jur. Foss., p. 19; Geol. 
N. J., Newark, 1868, p. 729. 
Shell much elongated ‘and slender, the apical angle in an uncompressed 
internal cast of large size being about 12°; volutions slightly convex on 
the exterior, when retaining the substance of the shell, nine or ten in num- 
ber, and marked on the surface by five or more sharply elevated spiral 
ridges, and apparently with finer lines on the interspaces and with fine 
transverse lines of growth crossing them. Sutures moderately distinct, 
but not channeled or grooved. Aperture unknown. On the cast the volu- 
tions are widely separated, indicating a considerable thickness of shell, and 
their form is obliquely rounded, larger and subangular near the lower mar- 
gin as they approach the lower end of the shell, but more distinctly circular 
and proportionally more slender in the upper part; probably from the 
greater thickening of the shell on the inside. The surface features are oaly 
indistinctly marked on the larger part of the casts, a single spiral groove 
in the upper part indicating a strong feature of the shell at this part. 
The specimens of this species which retain the surface features are 
very few and badly preserved, being mostly in a pyritous marl which rap- 
idly disintegrates on exposure. They are usually more or less compressed 
