THE NATIONAL INSTITUTION. 179 



«n 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 tlierc is every reason to believe a portion of 

 the high bank at Natchez belongs to the same geological period. On the Washita 

 fiver, Louisiana, the formation is well developed, near the town of Monroe ; and it 

 has also been discovered in Arkansas on Red river. 



G-eographicul range of the Medial Teriiary^ — I discovered many years since a 

 locality of this formation on Stow creek, Cumberland county, Now-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 otlier places 

 on the Eastern shore ; also, throughout the counties of St. Mary's, Calvert, &c.; 

 and on tho 'Western shore, in Virginia, the counties east of a line drawn from Tap. 

 pahaunock 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 Wnteree rivers, in South-Carolina, and this is as far as it has 

 yet been ti'acod south. 



Localities of tlie Upper Tertiary. — The first view of this formation,t which I ob. 

 tained, was on the Potomac river, a few miles above Point Lookout. Subsequently 

 I discovered another on the Ncuse 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-Carolina, 

 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 tke " Transactions of tlie Geo- 

 logical Society of Pennsylvania," vol. ii, page 336, and also the fossilliferous beds of Orangeburg, Soulli- 

 Carolina. The evidence was derived from organic remains collected by 0r. Wm. Blanding and Mr. 

 Vanuxem. Cylherea peronata, a conunon eocene species at Claiborne, is, perhaps, the most abundant 

 fossil of the burr stone. In my " Fossil SheJls 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, followuig the couree of the river." Shell Bluft", according to tlie observa- 

 tions of Mr. Vanuxem, is seventy feet high, formed of various beds of impure carbonate of lime. The 

 " Ostrea Georgiana," (which 1 believe Lo be O. longirostris, a fossil of the eocene near Paris,) is here in 

 a bed, n<-arly six fiet thick, in the upper part. A deposit of the same kind of oyster shells occurs near 

 Milledgivilie, in Georgia, accompanied by the Sculella quinquefaria, (Say,) imbeiUkd in while friable 

 limestone. Three parallel ridges of these oyster shells arc said to run from tlie Savauiiah to the Ala- 

 tamaha river. 



t For description of this locality, and list of fossils, see Journal of the Academy of Natural Sciences, 

 ToU vi, p. iOT, 1830. 



No. 2 15 



