372 
PALEONTOLOGY OF NEW YORK. 
Grammysia globosa. 
PLATE LXII, FIGS. 10-19. 
Grammysia globosa, Hall. Prelim. Notice Lamellibranchiata, 2, p. 57. 1870. 
Cardiomorpha cordatus, Hall. Pal. N. Y., vol. v, pt. 1. Plates and Explanations : PL 62, figs. 10-19. 1SS3. 
Shell below the medium size, sub-globose; valves sub-circular, or very broadly 
ovate; length a little greater than the height; basal margin regularly 
rounded, curving into the broad, rounded posterior margin. Cardinal line 
about half the length of the shell. Escutcheon strongly marked, limited on 
the exterior by a strong fold, with a smaller intermediate fold. Anterior end 
somewhat broadly rounded below the lunule, which is distinctly marked and 
sometimes margined by a narrow fold. 
Valves ventricose. 
Beaks at about the anterior third, very prominent and incurved. Umbonal 
slope rounded, not defined from the general convexity of the shell, sometimes 
with a narrow obsolescent fold. 
Surface marked by fine concentric striae and strong rounded or sub-angular 
concentric folds, which are sometimes duplicate, all becoming obsolete on the 
posterior slope. Interior unknown. 
Two specimens measure respectively 20 and 28 mm. in length, 20 and 23 
mm. in height, and 20 and 20 mm. in the depth of both valves. A larger 
specimen has a length of 33 mm. and a height of 27 mm. 
This species bears some resemblance to the shorter forms of G. arcuata, but 
differs in its ventricose character and circular form. Among all the collections 
which have been made no individuals have been noticed which are larger than 
those illustrated on plate lxiiA 
Formation and localities. In the shales of the Hamilton group, in Schoharie 
county; Leonardsville and Hamilton, Madison county, Pratt’s falls, Onon¬ 
daga county, and on the shores of Cayuga and Canandaigua lakes, N. Y. 
* The reference to the genus Cardiomorpha, as above cited, arose from copying an erroneous record of 
the species. At that time, the name Grammysia globosa, previously g-iven, was overlooked. 
