346 
PALAEONTOLOGY OF NEW YORK. 
This species resembles P. attenuata, but shows no constriction of the basal 
margin, and the beaks are more nearly central. 
Formation and localities. In the shales of the Chemung group, at Philipsburgli, 
Alleghany county, N. Y., and at Warren, Pa. 
Pal.eoneilo attenuata. 
PI,ATE L, FIGS. 34-39. 
Palceoneilo attenuata, Hall. Prelim. Notice Lamellibranchiata, 2, p. 12. 1S70. 
“ “ “ Pal. N. Y., vol. v, pt. 1. Plates and Explanations: PI. 50, figs. 34-39. 1883. 
Shell above the medium size, ovate-lanceolate in outline; length twice the 
height; basal margin gently curved in the anterior and posterior portions,, 
and sinuate a little behind the middle. Posterior extremity narrowly 
rounded. Cardinal line gently arcuate, declining posteriorly. Anterior end 
regularly rounded. 
Valves in the posterior part, depressed-convex, with a shallow depression 
in the middle; the anterior portion is more convex, becoming gibbous in the 
middle and above. 
Beaks a little in advance of the anterior third, small, little elevated above 
the hinge. Umbonal slope rounded, scarcely defined. 
Test thin, marked by fine, closely-arranged strife of growth, with stronger 
fascicles, at irregular intervals, which remain, in some degree, impressed upon 
the cast. 
The characters of the interior are shown in figs. 35 and 36 of plate 1. 
Three specimens measure respectively 20, 31 and 42 mm. in length, and 
10, 15 and 19 mm. in height. 
This species is readily distinguished by the elongate form, depressed-convex 
valves, and absence of the umbonal ridge and furrow. The only species with 
which it can be compared is P. elongata of the Chemung group. 
Formation and localities. In the Waverly sandstone, at Granville and Newark, 
Licking county, 0. 
