LAMELLIBRANCHIA TA. 
303 
distinctly angular, descending in nearly a direct line to the post-basal 
extremity. 
Test of moderate thickness; the cast is marked by fine concentric striaB, 
which are strongly fasciculate on the anterior portion of the shell, and regu¬ 
lar and uniform in strength on the post-cardinal slope. Interior unknown. 
The specimen described has a length of 72 mm. and a height of 35 mm. 
This species, compared with any other, has a much greater elevation of the 
umbo above the base of the shell, a larger anterior end and a more rapid 
declension to the post-basal extremity. The figure of this species given on 
plate xliv does not correctly represent the specimen. 
Formation and locality. In the Chemung group, near Franklin, Delaware 
county, N. Y. 
Goniophoea Chemungensis. 
PLATE XLIV, FIGS. 18, 20, 22. 
Cypricardites Chemungensis, Vanuxem. Geol. Surv. N. Y., Rep. Third Dist., p. 181, fig-. 2 ; p. 179. 1842. 
S'anguinolites Chemungensis, “ S. A. Miller. Cat. Amer. Pal. Foss., p. 202. 1877. 
Goniophora Chemungensis (Vanuxem), Hall. Pal. N. Y., vol. v, pt. 1. Plates and Explanations : PI. 44, 
figs. 18-22. 1883. 
Cypricardites carinifera, Conrad. Join-. Acad. Nat. Sci., Phila., vol. viii, p. 245, pi. 13, fig. 14. 1842. 
Shell large, trapezoidal; length two and one-lialf times the height; basal 
margin very gently curving, nearly straight, or slightly sinuate anterior to 
the middle ; posterior extremity obliquely truncated. Cardinal line straight, 
parallel to the base, extending for nearly two-thirds the length of the shell. 
Anterior end sloping rapidly from the beak and abruptly rounded below, 
limited by a very oblique, narrow, undefined sinus, which reaches the base 
more than one-third of the length from the anterior end. 
Valves moderately convex on the lower side, becoming gibbous in the 
umbonal region. Post-cardinal slope flat or slightly concave. 
Beaks sub-anterior, small and closely incurved, situated less than one- 
fourth the length of the shell from the anterior extremity. Umbo prom¬ 
inent. Umbonal ridge distinctly angular, extending in a direct line or with 
a gentle curvature to the post-basal extremity. 
