Notes on Cincinnatian Fossil Types 
323 
of one millimeter. Crania albersi was described from the Economy 
member of the Eden group at Cincinnati, Ohio. The fragment of 
rock supporting the Crania contains also traces of Cryptolithus 
tessellatus Green. 
Compared with Crania laelia Hall, from the Maysville and 
Richmond groups of Ohio and Indiana, Crania albersi is less rotund, 
has a more definite and straighter posterior margin, the apex is 
nearer this posterior margin, and the radiating striae are finer. 
31. Whitella cuneiformis, Miller 
{Plate VII, Figs. 1 A, B, C) 
1881. Orthodesma cuneiforme Miller, Jour. Cincinnati Soc. Nat. Hist., 3, p. 31 
Plate 8, Figs. 1, la 
1889. Sphenolium cuneiforme Miller, genotype, N. A. Pal., p. 513 
The type of Orthodesma cuneiforme is numbered 8803 in the 
Faber collection at Chicago University. It is labelled as coming 
from Versailles, in Indiana, and probably came from the Waynes- 
ville member of the Richmond formation. It evidently belongs 
to the group of shells typified by Whitella sterlingensis Meek and 
Worthen, for which Meek proposed the generic term Rhynchotropis, 
vithout describing this genus, however. Whitella sterlingensis is 
a typical fossil of the Maquoketa member of the Richmond, in 
Illinois and Minnesota. Whitella hindi Billings, from the Lorraine 
on the Humber river, at Toronto, in Ontario, belongs to the same 
group. 
This group of shells is characterized chiefly by the great elon- 
gation of the shell in a direction parallel to the umbonal ridge, the 
latter being strongly oblique to the hinge-line. The hinge-line ex- 
tends only a moderate distance anterior to the beak, and the ex- 
tension posterior to the beak is much shorter than the distance from 
the beak to the posterior termination of the shell along the umbonal 
ridge. Ventrally, the umbonal ridge rounds gradually into the 
general curvature of the shell as far as the ventral margin, but dor- 
sally the shell is strongly compressed, especially anteriorly, toward 
the beaks, so as to produce a flattened appearance when 
examined from above. Posterior to the beaks, there is a well 
defined escutcheon. 
