Fe 
Eocene Fossils of the United Sues. Q15 
one in the Eocene of Maryland, and four & Miocene strata. I 
once obtained a large recent species at. Mobile Point, Alabama, 
which | was lost betas I had determined its relation to others. I 
posterior ‘Tibaicy acutely rounded; beaks distant from anterior 
margin; anterior side of the umbo sibangulsied: (Plate II, fig. 2. ) 
Panopea elongata, Oon. ; 'Trans. Geolog. Soc. of Penn., Vol. 
i, p. 339, Plate XIII, fig. i. 
Piscataway, Md. 
Allied to Panopzea intermedia of Sowerby, but proportionally 
much longer, with more of a cuneiform posterior side, &c. It 
accompanies Pholas petrosa and Pholadomya Marylandica, con- 
sisting of indurated casts, coated with a portion of the shell. It 
is very abundant, having the valves connected, like the associated 
bivalves, proving that the species lived on the spot where it is 
now found. e stratum in which it is imbedded is the summit 
of the Eocene, and is of inconsiderable thickness. . It bears no 
evidence of having been deposited in agitated waters. 
LutTRaria. 
The genus Lutraria of Lamarck, was unknown to Deshayes 
in the European Eocene formation in 1833, but he noticed a few 
species in the Miocene strata. Sowerby has referred some shells 
of the Inferior Oolite, green sand-and chalk to this genus, but 
perhaps the hinge was not observed, and the generic character 
may be therefore doubtful. In this country, I find two species in 
the Eocene, and Say has described two recent species from the 
southern coast. In the Miocene strata, I have not met with the 
genus. The Post-pliocene of North Carolina, contains the recent 
L. canaliculata, Say. 
Lurrarta LAPIposa. Obliquely ovate, convex, with rather dis- 
tinct large concentric sulci, obsolete towards the base ; summits 
very elevated, from which the anterior and posterior dorsal mar- 
gins decline very obliquely ; anterior extremity angulated ; pos- 
terior side cuneiform towards the end margin, which is acutely 
rounded or subangulated ; anterior basal margin yery oblique, sub- 
truncated. (Plate I, fig. 7.) 
Orangeburg, 8. C. 
