OF SOUTH CAROLINA. 187 
ft Sand, below which water found, | 
} 9 feet, Quick-sand and clay, with occasional 
2 remains of trees. 
1 foot. | Sand and small shells. ; 
2 feet. | Gravel and oyster-shells. 7 
2 feet. | Mud and conchs. 
3 feet. | Fine close clay and young oyster-shells. : 
! 20 feet. | Pluff clay, with scales of mica. 
: 
: Sand, to Eocene beds. 
In the wells sunk near the Ashley, on the western side of the city, a bed of mud, containing 
stalks of the commen marsh grass, (Spartina glabra, Muhl.) is found, but this is evidently an exten- 
sion of the mud flats on the borders of the river, over which land has been made recently, and 
probably artificially. Although the fossilliferous bed, in the section, is eight feet in thickness, it is 
rarely found over four feet, as it is exposed along the coast. Fossils, no doubt, exist below this, but 
perhaps not so abundantly. Sections elsewhere on the coast differ but little from this: the fossil- 
liferous bed is overlaid by heavy beds of sand, which it is impossible to distinguish from those 
forming and undergoing various modifications along the coast at this moment. 
The formation extends from the coast about ten miles, where it thins out at an elevation above 
tide of a few feet. Its boundary is, of course, as irregular as that of the fossilliferous beds now accu- 
mulating beneath the waters of the Atlantic; indeed if the formation did not contain fossils no 
longer found living on the shores of South Carolina, it would be difficult to distinguish the two. 
On the coast of Horry District a bed is exposed on the beach, in which the shells, mixed with 
pebbles, are cemented by carbonate of lime, forming a solid rock. Some of the larger shells I 
found undergoing a change, from the ordinary structure to that of cale spar—not by solution and 
subsequent filling of the hollow casts with cale spar, but the substance of the shells appears to be 
undergoing a slow re-arrangement of the particles of which they are composed, whereby they are 
converted into crystallized carbonate of lime. I have specimens, in which this passage from one 
structure to the other is very evident. 
On Price’s Creek, not far from this locality, a bed of loose, disconnected valves of shells occurs, 
which is six feet thick. The shells are not water-worn, but resemble the beds of shells thrown up 
by storms, on the shore. It is about half a mile from the beach, and is elevated above tide, five 
feet. The shells are principally Venus mercenaria, Ostrea Virginiana,and Arca incongrua. I 
also found among them a West Indian Arca, and a species of Pectunculus. 
In All Saints, Georgetown District, I saw, on the main land, beds of oyster and other shells, 
belonging to this formation. But one of the most interesting localities is that at Laurel Hill Bluff, 
on the Waccamaw side of the peninsula, where the river, by encroachment, has produced a 
