OF DENISON UNIVERSITY. 
43 
There is no species known to us sufficiently resembling this one 
to require comparison. 
Genus Pal^oneilo. 
Much yet remains to be done in the way of comparative study of 
these perplexing forms of which our material is far from satisfactory. 
We are inclined to withdraw the name Goiiiodon^ provisionally used 
for some of these forms, though G.j. ohioense can hardly enter any of 
the genera as now limited. The hinge, however, probably had true 
teeth in an uninterrupted series. Our series begins in thq Bedford 
shales in northern and central Ohio, with a species of Palaeoneilo, 
called by Meek, P. bedfordensis, but which is very closely allied to 
Plamilton P. constricta. Something over one hundred feet higher we 
find our P. consimilis which somewhat resembles in outline P. maxima 
of the Hamilton. 
PALAEONEILO CONSIMILIS, sp. n. 
(Plate IV, Fig, 14.) 
Very similar to P. bedfordensis, but more elongate. Sub-ovate, 
produced posteriorly; length to height as 17 to 12 ; basal margin very 
convex opposite the beaks, curving regularly toward the front but 
straightened, almost sinuous, toward the narrowed posterior extremity; 
hinge declining from the beaks, which are near the anterior third ; sur- 
face rather flat with an obscure sinus posteriorly, marked by very fine 
concentric striae. Length, 17 mm., height, ii mm. This species 
connects P. bedfordensis with P. ignota and does not greatly differ 
from the extremely elongated varieties of P. constricta. 
When describing P. bedfordensis Mr. Meek refers to P. brevis of 
the Chemung as its nearest ally. Had he, however, compared it with 
P. constricta he might have hesitated to distinguish it. Compare, for 
example, our Fig. 8, Plate IX, with Fig. 3, Plate XLVHI, Vol. V, 
Pal. N. Y. The only difference appears to be the bolder sweep of the 
anterior outline in P. bedfordensis. 
Near Harlam, Delaware Co., O. 
