GASTEROPODA OF THE LOWER GREEN MARIS. 89 
to four in number; body volution large, forming about six-sevenths of the 
entire length, very gently convex throughout its entire length, except near 
the anterior end, where it becomes very slightly recurved; aperture very 
large, but narrow, acute above and below; columellar plaits unknown; sur- 
face of the shell marked by spiral ridges and by vertical lines; the former 
much the stronger and alternating in size where preserved sufficiently well 
to show; the vertical lines cut the spiral ridges so as to break them into 
nodes on the outer shell. 
This species closely resemble R. Teranus Conrad, but may be distin- 
guished by the shorter spire, which, in proportion to the length of the shell, 
is not much more than half as high as in that species. It.differs in the same 
respect from all the associated species and also in the more slender form 
than that of most of them; also in the strength of the markings. The cast 
of this species has not been recognized. It would most probably resemble 
that of R. angulatus more nearly than any other of the New Jersey forms, 
but would differ in the length of the spire and in the more symmetrical 
body volution. TO . 
"This species has usually been included under the Voluta Conradi ot 
Gabb, by collectors, as also were those herein described under the names 
V. ponderosa and V. Gabbana. I had for some time concluded to unite all 
but the last-named one as varieties of the one species V. Conradi, but upon 
studying a number of them together the differences appear so great that it 
seems unreasonable in a group where the resemblances are so great among 
the species as in the Volutide that so great a diversity should be allowed, 
and I have concluded to separate under three names what I had originally 
classed as one species, and I think they are properly specifically distinct. 
Formation and locality: In the Lower Green Marls at Holmdel, New 
Jersey, in Prof. Reiley’s collection; and at Freehold in the Rev. Dr. Schank’s 
collection. Cabinet at Rutgers College. 
VOLUTODERMA and VOLUTOMORPHA Gabb. 
In Mr. W. M. Gabb’s synopsis of the Volutide’ he describes these two 
genera, including them among the Volutes. On another page I have shown 
some reasons for believing Volutomorpha more nearly related to fasciolaria 
1 Proc, Acad. Nat. Sci., Phila., 1876. 
