THE NATIONAL INSTITUTION 
189 
posed by many to have been distributed along shore by the Indians. These abound 
on the Patuxent, in St. Mary’s county, as well as in many places throughout the 
tertiary region of Maryland and Virginia. Major Southron, who resides below Bene- 
diet, on the Patuxent, informs me that he has seen them in a bed ten feet thick; 
and on the Wicomico, it is said, they occur thirteen feet in thickness, covering many 
acres. The objections to these being deposits by Indians are at least worthy of 
notice, and may serve to stimulate inquiry. In the first place, the beds are of con¬ 
siderable extent, often at some distance from the water courses, and of no greater 
variation in thickness than the marine deposits of the more ancient tertiaries. 
Many entire shells are found among the unconnected valves. They are sometimes 
imbedded in sand, and others in a black mould, such as would be formed by the 
mud of estuaries mixed with lime, from the decomposing shells. These beds are 
always beneath the soil covered originally by the forest. At Easton, on the Eastern 
shore of Maryland, fragments of extinct species of Pecten are found among them. 
On the south shore of Raritan bay, the shells occur in a regular stratum, generally in 
single valves, mixed with an occasional specimen of Fulgur r.analiculatus, just in 
proportion to the living individuals of both species in Raritan bay. On the Chesa¬ 
peake, below the Patuxent, they occur at least eight feet below the surface of the 
country around, and were traced in a continuous deposit of nearly uniform thickness, 
about four miles in extent. The position and character of these deposits correspond 
with those of the Gnathodon on the Potomac, which might w T ith just as much rea¬ 
son be referred to Indian agency, as well as the immense accumulation of the same 
shells for hundreds of miles along the northern shore of the Gulf of Mexico, in 
which it is said that Indian idols or small images have been found. Mr. Abel, who 
resides above Town creek, on the Patuxent river, informs me, that oyster shells, 
many of them with the valves in apposition, are found in his vicinity, in a bed two 
feet thick, ten feet beneath the surface. I shall not at present pursue this subject, 
intending to investigate it more leisurely at a future period, when I design to pub¬ 
lish a more detailed history of these interesting beds. In conclusion, two important 
deposits of the upper tertiary will be noticed. One on the Potomac, near its 
junction with the Chesapeake bay, and the other on Neuse river, N orth-Carolina. 
The first of these was described by me in 1830, in the journal of the Academy of 
Natural Sciences, of Philadelphia, in which paper appeared the first attempt to clas¬ 
sify and describe any of the tertiary formations of North-America. 
Section near the month of Potomac. 
Elevation fifteen feet. 
Chesapeake. 
Sand and gravel. 
1 foot 
thick. 
Ostrea virginiana , Mytilus hamatus, (estuary deposit,) sand. 
8 feet 
above 
tide. 
f Pholas costata, Mactra lateralis, 
Clay with Area transversa, Solecurtus caribceus , (ma- 
L rine deposit.) 
