GASTEROPODA OF THE LOWER GREEN MARLS. 163 
Gabb, from which it is very difficult to distinguish it. The specimens of 
that species used by Mr. Gabb are, however, a little more slender or pointed 
in the lower part. 
Formation and locality: In the Lower Green Marls at Crosswicks, New 
Jersey. Collection Acad. Nat. Sci., Phila. 
Genus AVELLANA D’Orb. 
AVELLANA BULLATA. 
Plate xx, Figs. 1-4. 
Tornatella ? bullata Morton: Synop. Org. Rem. Cret., p. 48, Pl. v, Fig. 3. 
Solidula bullata (Morton) Gabb: Synopsis, p. 81; Meek, Check List Cret. and Jur. 
Foss., p. 17; Geol. N. J., Newark, 1868, p. 728. 
Shell large for the genus, attaining fully an inch in length; very 
globose, the diameter being nearly as great as the height, at least equal- 
ing seven-eighths of the height. Spire low and rounded, and the base 
only slightly more pointed. Volutions between three and four in num- 
ber, the outer half of the last one more abruptly deflected downward at 
the suture than the preceding ones, but again elevated near the aperture. 
Aperture narrow, pointed above and widest below and rounded; the length 
equal to about four-fifths of the entire length of the shell; columellar 
margin thickened and marked by horizontal ridges on the upper two- 
thirds of its length, and by two very strong, ridge-like teeth or plica- 
tions below the middle, the upper of which is the stronger. Base and 
outer lip slightly thickened. Surface of the shell, as shown on the cast, 
marked by fine spiral lines, and by transverse lines of growth. Of the 
spiral lines about thirty may be counted on the outer half of the body whorl 
of the larger individual, those near the base being coarser than those above, 
but gradually becoming fainter in strength. On one of Dr. Morton’s types 
the transverse lines are regular and but little less strongly marked than the 
spiral lines, so that the surface under a glass looks to be cut up into small 
nearly equal solid nodes. 
The species is remarkable for its large size and globose form, and also 
among the New Jersey forms for the strong columellar folds or plaits, the 
upper of which is much the largest. The horizontal line-like granules of 
