Tertiary Strata of the Atlantic Coast.. 109) 
bors of Charleston and Newport, as the recent shells of those har- 
bors accord remarkably with the fossils of the medial Pliocene; but 
the older Pliocene appears to have been of deep sea origin, deposit- 
ed beyond all influence of currents setting from the rivers into the 
sea. ‘The newer Pliocene on Mr. Benners’ plantation exhibits some 
striking points of difference to the Potomac beds, in the enclosed or- 
ganic remains, embracing a far greater number of species, a few of 
which are extinct or unknown, common also to the medial Pliocene 
strata; whilst not one of the lost species of the latter occurs in the 
newer sands and clays of the Potomac locality. ‘The recent shells 
of the Atlantic, in a line east from the mouth of the Potomac, do 
not vary much from those of North Carolina, east of Newbern, and 
yet to contrast the two fossil localities alluded to, I will observe that 
the latter, contains forty species not found in the former, and also a 
much greater proportion of tropical shells. 
List of fossil shells found at Mr. Benners’: (Newer Pliocene. ) 
Crepidula fornicata, Lam. Cytherea albaria, Say. 
plana, Say. Venus cancellata, Lin. 
Cerithium. Crassatella undulata, Say. ” 
Fusus cmereus, Say. Arca ponderosa, Say. 
Fulgur carica, Say. transversa, Say. 
canaliculatus, Say. limula, Conrad. 
Buccinum avarum, Conrad. pexata, Say. 
Terebra dislocata, Conrad, Tellina alternata, Say. 
Nassa trivittata, Say. -— (new). 
Natica duplicata, Say. —- (new). 
Fasciolaria mutabilis, Conrad. | Sanguinolaria fusca, Conrad. 
Oliva litterata, Lam. | Mactra lateralis, Say. 
-. — solidissima ? Chem. 
Marginella. — tellinoides, Conrad. 
Ranella caudata, Say. Cardium magnum, Born. 
Fusus 4-costatus, Say. Lutraria canaliculata, Say. 
Vermetus lumbricalis, Lam. Pecten concentricus, Say. 
Scalaria lineata, Say. —- purpuratus, Lam. 
Bullina canaliculata, Say. - eboneus, Conrad. vf 
Arthemis concentrica. Nucula limatula, Say. f 
Chama arcinella, Lam. - proxima, Say. 
Chama ———. Cypricardia arata, Conrad. 
Cytherea Sayana, Conrad. Anomia ephippium, Lin.,, 
