176 PALEONTOLOGY OF NEW JERSEY. 
One single specimen is somewhat shorter than common, in proportion to the 
height of the spire, but this may only be an individual peculiarity; at least 
the difference is not sufficiently marked to warrant any specific separation. 
Figures of the best preserved individual have been given on PI. xx1 of the 
Middle Marl species for comparison with those from the Lower Marls. 
SCALARIIDE. 
Genus CAVOSCALA, n. gen. 
Shell scalariform, thin in substance, with numerous round contiguous 
volutions, which are crossed by oblique, raised varices. Surface cancellated, 
axis broadly perforate, the umbilicus wide, angular on the margin and show- 
ing the inner volutions. Base of body whorl margined by a broad flattened 
band. Aperture subcircular obliquely straightened on the inner side. Type 
C. annulata, Morton’s sp. Upper Cretaceous. 
The species upon which this genus is based is the only one known 
Externally it resembless the living shell Scalaria pretiosa Linn., except in the 
connected volutions; more numerous varices; cancellated surface and wide 
umbilicus; the latter feature being Solarium-like in character, and also in 
the broad flattened space extending from the margin of the umbilical cavity 
to the outer basal portion of the whorl, where it terminates in an abrupt 
shoulder which limits the next volution and forms a carinated suture. 
The oblique varices and the fine transverse strize both cross this space and 
are slightly visible in the umbilicus. The aperture is imperfect in all the 
examples seen (seven), but of course the margin would be thickened and 
bordered at each varix, so that it would present the appearance of a thick- 
ened rim or peristome, but not larger or heavier than the other varices, as 
in some forms of Scalaria. 
