50 EE. Desor on the Post-Pliocene of the Southern States. 
The main features of the Post-pliocene of South Carolina are 
thus defined by Mr. Tuomey.* _ It is confined to a belt along the 
coast of about eight or nine miles in breadth. The fossils are 
nearly all referable to living species now inhabiting the coast; a 
few however belong to the fauna of Florida and the West Indies. 
As to its elevation, M. Tuomeyt+ is of opinion that along the 
whole line of the coast of South Carolina it does not exceed eight 
eet. “There isno sudden break any where separating it from the 
beds now in progress of deposition, for it dips gently under the 
waves of the ocean, and the fossils are often found mingled with 
living species. So life-like indeed do the shells appear, that it 
requires the presence of forms no longer inhabitants of the coast, 
to satisfy one that he is not looking at a recent shell-bed.” Like 
the fossils of the Laurentian along the Kennebec, the shells have 
even retained their specific colors and markings. 
e have already stated, on Sir Charles Lyell’s authority, that 
this formation extends uninterruptedly to the mouth of the Neuse 
in North Carolina. There indeed, Mr. Conrad long since described 
a deposit of Post-pliocene, with thirty-four species of marine shells, 
all identical with those of South Carolina. He found here also 
the Ginathodon cuneatus, a species inhabiting brackish water, to- 
gether with remains of terrestrial animals. 
The portion of the coast north of the Neuse, between it and 
the Chesapeake Bay, bordering on Albemarle Sound and James 
River, has not as yet been sufficiently examined to allow us to 
indicate the precise boundaries of the various tertiary and quarter- 
nary formations. There is, however, little doubt that the Pine- 
barrens belong to the most recent deposits; and it would seem 
that the Post-pliocene occupies here a much wider belt than it 
does farther south beyond the Neuse. 
As to Chesepeake Bay itself, it has been ascertained that the 
deposits upon its borders belong, partly at least, to the Post-plio- 
cene. As early as 1830, Mr. Conrad called attention to a remark- 
able deposit of this description at the mouth of the Potomac, 
which he designated then as upper tertiary.§ The same natural- 
ist published in 1842, in the proceedings of the National Institute, 
the following list of shells collected there. I 
‘ * Report on the Geology of South Carolina, p. 212. 
+ Ibid., p. 188. 
j Am. Journ. of Arts and Sciences, Proc, of the National Institution, 1842, p. 190. 
5 Journal of the Academy of Natural Sciences of Philadelphia, 1830. i 
| It has been a matter of much controversy whether the oyster beds which occur 
in a sub-fossil state on the Patuxent and in many other places the low level 
plains t to the creeks and rivers along the coast of the mid 
to the same formation, as it is suppose Mr. Conrad, or whether are 
agency. As a proof that they were not collected by Indians, it is stated that 
at the month of the Po they _by the diluvium, true would 
at once settle the question. It is m tated by Mr. Conrad that the character 
and position is to correspond with the 
