PALAEONTOLOGY OF NEW-YORK. 
Geological formations and localities. This species occurs in the Schoharie grit, 
in Albany and Schoharie counties, usually of medium size and well marked cha¬ 
racters, and sometimes attaining larger dimensions. It occurs in the limestone of 
the Upper Helderberg, in Albany and Schoharie counties, and at nearly all the 
localities of that rock as far as the Niagara river; particularly at Clarence and 
Williamsville in Erie county. It is found at several localities in Canada West 5 
also at the Falls of the Ohio and at Columbus and Millford, Ohio, and probably 
at Sandusky and other localities of the Corniferous limestone in the West. Some 
large imperfect valves in the Hamilton shales of Centra^ New-York may probably 
be of this species. 
Meriste!JaL§citiila. 
PLATE XLVII. 
Atrypa scitula : Hall, Geol. Report of the Fourth District New-York, p. 171, f. 1. 1843. 
Not Alhyris (?) scitula : Hall; Billings in Canadian Journal (n. s.), No.xxvii, p. 278, f. 35 &, 36. 
1860. 
Charionella circe : Billings, Canadian Jour, (iv s.), No. xxxviii, p. 273, f. 100. 1861. 
Not Terebratula circe, Barrande ( Spirigera circe, d’Orbigny), Naturwissenschaftliche Abhandl., 
pa. 393, pi. 10, f. 6 (1857), which is apparently congeneric, and a true Meristella. 
Shell ovate or ovate-spatulate, compressed towards the base. 
Ventral valve the more convex, sometimes gibbous above the middle, 
depressed in the lower part; umbo prominent, with the beak elevated 
and incurved above the umbo of the opposite valve. The shell curves 
gently to the base and baso-lateral margins, but becomes abruptly 
incurved above the middle, and concave on each side for some distance 
below the beak; the proportions of breadth above are as six to five, or 
seven to six. 
Dorsal valve depressed convex in the lower part, more convex and 
somewhat gibbous above the middle; beak small and rather prominent. 
Surface marked by fine concentric striae, which, from the usual partial 
exfoliation of the shell, are often scarcely perceptible : more rarely 
1 some remains of obsolete interrupted radiating striae are perceptible. 
The shell, as it usually occurs, is smooth and glabrous. 
This species has the usual features of others of the genus. It differs from M. doris 
in being less gibbous, with a lesser arcuation of the ventral valve, the upper 
■part less elongate and attenuate, and a less extensive flattening of the sides of the 
shell. 
