172 GEOLOGICAL SURVEY 
out in a bed of blue clay, containing Mactra lateralis in great abundance ; and is the only deposit 
in the State that reminded me of the Virginia Miocene. Resting upon the marl, is a bed of marsh 
mud, two or three feet thick, which is but an extension of the marshes on the shore, a few miles 
lower down. Superimposed upon this is a bed of incoherent sand, similar to the loose, moving 
sands along the coast, but now rendered permanent by the growth of plants, including large live- 
oaks. Immediately under the mud the marl is quite ferruginous, but lower it assumes a bluish tint. 
The calcareous portion is between eight and twelve feet in thickness. 
I saw this bed exposed higher up the river, at Mr. Bessant’s, where it occupies the bed of the 
stream, and still higher, some distance inland, at Mr. Vaught’s, where it occurs six or eight feet 
below the surface. 
At the mouth of the river I collected Pliocene and Cretaceous fossils, mingled together, as they 
were thrown up by the waves, on the shore—showing that these formations extend under the 
waters of the Atlantic. At Capt. Randal’s the water is sufficiently salt to make it habitable to 
Ostrea Virginiana, Fusus cinereus, Buccinum trivitatum, B. obsoletum, and other littoral molluses. 
I collected, at these localities, the following fossils. 
Brachiopoda.* 
Infundibulum depressum, Flusus cinereus. 
Crepidula fornicata, Pyrula carica, 
Natica duplicata, Oliva litterata. 
“  Caroliniensis, Conus adversarius, 
Trochus philantropus, Columbella avara, 
Turritella alticosta, Marginella limatula, 
Cyprea pediculus.t 
Lamellibranchiata. 
Pholas turgidus, Cytherea Sayana, 
Solecurtus caribeus, Artemis acetabulum, 
Myalina subovata, Venus cribraria, 
Mactra lateralis, Carditamera arata, 
Donaz variabilis, Pectunculus subovatus, 
Astarte concentrica, : 5—rugatus, 
radians, Chama congregata, 
Ostrea Virginiana. 
Making, in all, 28 species, of which 14, or about 50 per cent. are now living: eleven on the coast of 
South Carolina, one on the northern coast, and one belongs to the Fauna of the coast of Florida 
and the West Indies. 
Between the Waccamaw and the coast the land consists of undulating sand-hills, not unlike 
those immediately on the coast. The marl is hid by these, nor is it seen until they are cut through 
by the river, although numerous lime-sinks indicate its presence below the surface. 'The lowest 
point on the river at which the Pliocene marl is seen, is at Grissett’s Landing, a few miles above 
* Those in italics are recent. 
+1 was not a little surprised to find this little W. Indian species among these fossils, 
