204 REMARKS ON FOSSILS OF PERMO-CARBONIFEROUS AGE, 



Sp. char. — Shell of median size, practically equilateral, higher 

 than wide, hinge line apparently as wide as the shell ; valve, 

 seemingly the right, faintly convex, with rather large triangular 

 ears, the anterior slope abrupt and steep ; umbo well marked and 

 prominent ; surface bearing from twenty to twenty-two radiately 

 curved, coarse, or rough-looking entire costse, with a smaller 

 interpolated rib separating each pair, and hardly reaching the 

 umbo ; the whole crossed by growth laminae, the primary costae 

 apparently becoming spinous at the points of intersection. 



Obs. — The principal characters of this species are its shape, the 

 number and arrangement of the costae, and the steep anterior 

 slope above the anterior ear. On the whole, it appears to corres- 

 pond with the above little-recognised species, but which, I have 

 reason to believe, is much more common in the Permo-Carbonifer- 

 ous beds of N. S. Wales than is generally supposed. 



Genns PETERINEA, Goldfuss. 



Pterinea macroptera, Morris* 



P. macroptera, Morris, in Strzelecki's Phys. Descrip. N. S. 

 Wales, &c., 1845, p. 276, 1. 13, f. 2 & 3. 



Obs. — A single example, much defaced by a peculiar fused or 

 semi-enamelled aj)pearance common to most of the fossils from 

 Ironstone Ridge, possesses many of the characters of this species, 

 such as the convex body, large posterior wing, coarse concentric 

 rugae, and well-marked ribs. The anterior margin, however, is 

 rather defective, and in consequence the characteristic curve of 

 the projecting anterior end is not visible. I think it may be 

 regarded as a small individual of this species. It measures 

 2 inches by 1^-. 



* This species has no real relation to the genus Pterinea as now restricted. 

 It will shortly be pubhshed by the writer as the type of a new genus. 

 Merismopteria. 



