360 PALEOZOIC PALEONTOLOGY. 
Actinopteria insiginis have been observed in the Orbiculoidea jervensis 
fauna of the Oriskany. Associated with them are fragments of other 
winged shells, which may belong to some other species of the same 
genus or to Pterinea. 
ACTINOPTERIA TEXTILIS (Hall) var. ArENARIA (Hall). 
Pilateine Bios ie 
1859. Avicula tertilis var. arenaria Hall, Pal. N. Y., vol. IIL, p. 465, 
pl. 109, figs. 1-2, pl. 110, fig. 2. 
Description.—Shell large, obliquely subovate, the proportions of 
length and height variable. Left valve becoming moderately and 
regularly convex from the base, the greatest convexity being about 
the first third below the hinge-line. Posterior wing large, extending 
along the margin of the body of the shell half way from beak to base. 
Anterior wing small, triangular, wrinkled. Surface marked by strong, 
radiating ribs, sometimes regularly dichotomosing and subequal, and 
in other specimens quite unequal, showing a few stronger ribs, with 
several finer ones between, and these are crossed by strongly-elevated, 
imbricating lamellae. The right valve is slightly concave, smaller than 
the other, faintly marked by the radiating ribs, which sometimes are 
scarcely scen. 
Remarks.—More or less fragmentary specimens of a species of 
Actinopteria, which are quite certainly representatives of this common 
Oriskany species of the genus, are of not uncommon occurrence in 
the Oriskany formation in New Jersey. Some specimens, when com- 
plete, must have had a height of 75 mm. or more. 
MEGAMBONIA BELLISTRIATA Hall. 
Plate: Ue bigs 
1859. Megambonia bellistriata Hall, Pal. N. Y., vol. IT1., p. 467, pl. 
109, fig. 4. 
Description —Left valve subsemi-elliptical in outline, height and 
width subequal; hinge-line less than the greatest width; the beak a 
