496 
PALAEONTOLOGY OF NEW YORK. 
become almost parallel to the cardinal border, while in that species the striae 
terminate abruptly at the cardinal line. 
Formation and locality. In the central portion of the Hamilton group, near 
Geneva, N. Y. 
Glossites depressus, n. sp. 
PLATE XL, FIGS. 15, 17 ; AND PLATE XCVI, FIG. 12. 
In part Modiomorpha ? avvygdalina (Winchell), Hall. Prelim Notice Lamellibranchiata, 2, p. 78. 1870. 
“ “ “ “ “ Pal. N. Y., vol. v, pt. 1. Plates and Explana¬ 
tions : PI. 40, figs. 12-20 1883. 
Not Sangidnolites amygdalimis, Winchell. Proc. Acad. Nat. Sci., Phila., p. 13. 1863. 
Shell above the medium size, sub-elliptical, wider behind ; length about twice 
the height; basal margin gently curved to near the extremities, where it 
rapidly recurves. Posterior extremity abruptly rounded, obliquely sub¬ 
truncated on its upper portion. Cardinal margin gently arcuate for its 
entire length. Anterior end slightly produced, rapidly declining from the 
beak and narrowly rounded below. 
Valves depressed-convex in the posterior and basal portions, becoming 
moderately convex in the umbonal region. 
Beaks sub-anterior, small and closely appressed, scarcely rising above the 
hinge-line. Umbonal slope not defined. 
Surface marked by fine concentric strise, which are fasciculate upon the 
middle and posterior portions of the shell, producing undulations of the sur¬ 
face which are sometimes strongly marked in the cast. 
Anterior muscular impression shallow, close to the anterior margin. 
One of the specimens described has a length of 50 mm. and a height of 26 
mm. A smaller individual measures 47 mm. in length and 24 mm. in height. 
This species closely resembles G. lingualis, but the anterior end is propor¬ 
tion allv shorter and the valves are more expanded posteriorly. 
Formation and localities. In the shaly sandstones of the middle portion of the 
Chemung group, at Buck’s quarry, north-west of Elmira, associated with Orthis 
impressa ; and near Elmira, associated with Orthis Tioga and Leptodesma protextum. 
