Grove," near the mouth of the river, it appears in the fonn of a 

 soft pulverulent limestone, in which two species of Scutella, ( S. ma- 

 crophora Ravenel, and anotlier,) are very abundant. The soft 

 limestone had been cut through to the depth of five feet in digging 

 a canal, situated near " the Grove," about seventeen miles north of 

 Charleston ; its thickness here is unknown. I found in it Pecten 

 Lyelli Lea, a Claiborne shell, and the upper valve of an oyster, 

 M'hich seems undistinguishable from 0. bellovacina ; also a species 

 of Lucina, and a large Pecten allied to P. pleuronectes ; also a 

 species of Spatangus common to the limestone of the Santee 

 canal. 



At the Rock Landing, near the Grove, the white limestone is 

 composed of triturated shells, and assumes a very hard and solid 

 form. It contains fragments of Echinoderms, casts of shells, and 

 corals {Lunulite ?) : it sometimes passes into an imperfect oolite. 



Between the Grove and Vance's Ferry on the Santee River, a 

 distance of about forty miles, is a continuous formation of white 

 limestone, which I examined in company with Di\ Ravenel, first 

 at Strawberry Ferry and Mulberry Landing, then on the banks of 

 the Santee Canal, and afterwards at Wantoot and Eutaw. I then 

 followed it in a north-westerly direction for twelve miles, by Cave 

 Hall and Streeble's Mill, to near Halfway Swamp, On reaching 

 Stoudenmire or Stout Creek, a ti'ibutary of the Santee, we found 

 the limestone and marl to disappear beneath a newer deposit, also 

 referable to the eocene period, of which I shall afterwards speak as 

 the burrstone formation. 



The soft limestone varies in hardness, passing frequently into a 

 white marl, and resembling in texture some of the craie tufaii of 

 the Loire in France. It consists almost entirely of comminuted 

 shells or corals, but it rarely exhibits any laminse of deposition, 

 and even where it attains a thickness of twenty or thii-ty feet, 

 there would be a difiiculty in determining whether it were hori- 

 zontal, if a bed of oysters, 0. sellcBformis, like that at Vance's 

 Feriy, did not occasionally occur. Notwithstanding its slight 

 elevation above the sea, the Santee limestone cannot be less than 

 120 feet thick at Strawberry Ferry, being vertically exposed to 

 the extent of 70 feet on the low banks and bottom of Cooper River, 

 and to the height of 50 feet above these banks in the neighbouring 

 hills. Its upper surface is very irregular, and is usually covered 

 with sand, in which no shells have been found. 



At Eutaw and other points, corals of the genera Idmonea, Den- 

 drophyllia, Flabellum, Tubulipora, Hippotlwa, Farcimia, Vincu- 

 laria, Eschara, and others, occur, with a species of Scalaria, and 

 other shells. These fossils, and the rock containing them, reminded 

 me so much of the straw-coloured limestone of the cretaceous 

 formation which I had seen on the banks of Timber Creek in New 

 Jersey, that I do not wonder that some error has arisen in con- 

 founding the tertiary and secondary deposits of the Atlantic 

 border. The species, however, prove, on closer inspection, to be 

 different. This litholoa;ical resemblance led to the admission into 



