THE NATIONAL INSTITUTION. 
.179 
<on the James river, two miles below City Point. In Georgia, in several of the eastern 
counties, burr stone of the lower tertiary period prevails.* On the Chatahoochie 
-river, near Fort Gaines, is a cliff similar to that at Claiborne. Near Black’s Bluff, 
in Wilcox county, Alabama, at Claiborne and St. Stephen’s, are the only localities 
yet known in that State. In Mississippi, I recognise the formation by fossils from 
the Walnut Hills and Vicksburg, and there is every reason to believe a portion of 
the high bank at Natchez belongs to the same geological period. On the Washita 
river, Louisiana, the formation is well developed, near the town of Monroe; and it 
has also been discovered in Arkansas on Red river. 
Geographical range of the Medial Tertiary .—I discovered many years since a 
locality of this formation on Stow creek, Cumberland county, New-Jersey, the 
most northern limit with which we are yet acquainted. In Maryland, it occurs 
near Chestertown, Wye Mills, on Choptank river near Easton, and other places 
on the Eastern shore; also, throughout the counties of St. Mary’s, Calvert, &c.; 
and on the Western shore, in Virginia, the counties east of a line drawn from Tap. 
pahannock to Murfreesborough, are chiefly of this formation, which continues 
through North-Carolina, in all the eastern counties. It occurs near the junction 
of the Congaree and Wateree rivers, in South-Carolina, and this is as far as it has 
yet been traced south. 
Localities of the Upper Tertiary. —The first view of this formation,! which I ob¬ 
tained, was on the Potomac river, a few miles above Point Lookout. Subsequently 
2 discovered another on the Neuse river, below Newbern, in North-Carolina, resting 
upon the medial tertiary; and on the Potomac, in St. Mary’s county, Maryland, is 
a bed of Gnathodon of the same geological age. Many of the deposits of Ostrea 
virginiana found in various places over the medial tertiary strata, are referable to the 
same period. On the shore of the Chesapeake, below the Patuxent river, is another 
locality. The same formation underlies the city of Charleston, South-Carolinaj 
and is penetrated by some of the wells. Dr. Emmons has discovered on the borders 
of Lake Champlain and elsewhere, in the northeastern section of New-York, fossils 
* This burr stone was referred by me to the eocene period in 1835, in the “ Transactions of the Geo¬ 
logical Society of Pennsylvania,” vol. ii, page 336, and also the fossilliferous beds of Orangeburg, South- 
Carolina. The evidence was derived from organic remains collected by Dr. Win. Blanding and Mr. 
Vanuxem. Cytherea peronata, a common eocene species at Claiborne, is, perhaps, the most abundant 
fossil of the burr stone. In my “ Fossil Shells of the Tertiary formations of the United States,” (1835,) 
page 31, the following notice of the lower tertiary occurs: “ From Vance’s ferry, the line of the 
eocene runs a little to the south of west, and, passing through the town of Orangeburg, crosses Sa¬ 
vannah river at Shell Bluff, which is its boundary on the west. This formation appears, at intervals, 
in a distance of forty miles, following the course of the river.” Shell Bluff, according to the observa¬ 
tions of Mr. Vanuxem, is seventy feet high, formed of various beds of impure carbonate of lime. The 
“ Ostrea Georgiana,” (w-liich I believe to be O. longirostris, a fossil of the eocene near Paris,) is here in 
a bed, nearly six feet thick, in the upper part. A deposit of the same kind of oyster shells occurs near 
Milledgeville, in Georgia, accompanied by the Scutella quinqnefaria, (Say,) imbedded in white friable 
limestone. Three parallel ridges of these oyster shells are said to run from the Savannah to the Ala- 
lamaha river. 
t For description of this locality, and list of fossils, see Journal of the Academy of Natural Sciences, 
vol. vi, p. 207, 1830. 
No. 2 15 
