344 
PALAEONTOLOGY OF NEW YORK. 
PALiEONEILO ANGUSTA, n. Sp. 
PLATE XCXII, FIG. 11. 
Shell below the medium size, elongate, sub-elliptical; length about twice the 
height; basal margin regularly curving. Posterior extremity produced, 
obliquely sub-truncate and doubly emarginate. Cardinal line straight and 
long. Anterior end comparatively large and broadly rounded. 
Valves very moderately convex below, scarcely gibbous in the middle and 
above. 
Beaks at about the anterior third, low, closely appressed, rising but little 
above the hinge-line. Umbonal slope defined, sub-angular, extending to the 
post-inferior extremity. Post-cardinal slope broad, and marked longitudinally 
by a distinct angular fold reaching to the posterior margin. 
Surface marked by fine concentric striae; and on the upper anterior por¬ 
tion, the umbo and post-cardinal slope, by regular somewhat distant lamellose 
elevations. 
Two specimens measure respectively 20 and 26 mm. in length, and 10 and 
13 mm. in height. 
In its elongate form it bears some resemblance to P. muta, but the post-car¬ 
dinal slope is narrower, the ridge along this slope is stronger and more nearly 
central and the posterior extremity is doubly sinuate. 
Formation and locality. In the Chemung group, near Elmira, N. Y. 
PALiEONEILO BISULCATA. 
PLATE L, FIGS. 12-14. 
PalcBonello bisulcata. Hall. Prelim. Notice Lamellibrancliiata, 2, p. 10. 1S70. 
“ “ “ Pal. N. Y., vol. v, pt. 1. Plates and Explanations: PI. 50, figs. 13, 11. 1SS3. 
Shell small, broadly sub-ovate; length nearly one-lialf greater than the height; 
basal margin regularly curving to the post-inferior extremity. Posterior mar¬ 
gin sinuate, obliquely sub-truncate. Cardinal line arcuate. Anterior end 
regularly rounded. 
