186 GEOLOGICAL SURVEY 
of the ocean has been converted into dry land. We can see, at a glance, the first steps in the fos- 
sillization of the remains of organic beings, and the manner in which they became embedded in 
the solid rocks where we find them. Whatever doubts persons may have, who have paid but little 
attention to the subject, as to the connection between fossils and living forms, here they can have 
none; for the fossil shells of mollusca have their specific colors and markings as well preserved as 
those of their descendants, now living along the coast. 
The P. Pliocene of the southern Atlantic coast has not received the attention it deserves. Mr. 
Conrad has published an account of the formation in Maryland, with a list of 27* fossils from a 
deposit at the mouth of the Potomac, and pointed out the interesting fact that a few of them were 
only found alive on the southern coast, or on that of the Gulf of Mexico. He also describedj a 
similar deposit on the Neuse, in North Carolina, accompanied by a list of 34 fossils. He found 
here also ‘Gnathodon cuneatum, together with the remains of terrestrial animals. 
Mr. Lyell examined, and published his views on, portions of the formation on the coast of 
Georgia and South Carolina, and corroborated the statements of those writers who supposed that 
they had seen evidences of subsidence of the coast, of very recent date. 
In a “Memoir on the Megatherium and other extinct gigantic quadrupeds of the coast of Georgia,” 
&c. read by William B. Hodgson, Esq. before the National Institute, all that was known of this 
formation and its embedded fossils is presented in a lucid and interesting form, accompanied by 
illustrative drawings and maps. As this paper embodies the substance of the investigations of 
J. H. Couper, Esq. as well as those of Dr. Habersham, it must be read by those who would have 
clear views of this portion of Southern Geology. 
Mr. Vanuxem, I believe, first noticed the existence of this formation in South Carolina, and 
carried some of the fossils taken from a well in Charleston, to Philadelphia. Myr. Ruffin, in his 
Report, published a list of 25 species of fossils, prepared for him by Prof. L. R. Gibbes, from beds 
in the vicinity of the city. 
The coast of South Carolina offers excellent opportunities for studying this formation, as it has 
not suffered much from denudation, and is sufficiently exposed for examination where it is inter- 
sected by the rivers and streams that flow into the Atlantic. It is composed of beds of sand, clay, 
and mud, containing fossils—the whole amounting, probably, to about 60 feet in thickness, overlap- 
ping the Pliocene beds on the coast of Horry and Georgetown, and on the rest of the coast, those 
of the Eocene. 
The strata immediately under Charleston are often cut through when wells are sunk. A section 
of one of these wells, which I owe to Mr. Rogers, who has had much experience in their construc- 
tion, presents the following order in the superposition of the beds. 
*Proc. Nat. Inst. +Am. Jour. Sci. and Arts. 
