174 
PROCEEDINGS OF 
Alabama, and is, perhaps, the most unvarying and curious in shape, and cer¬ 
tainly one of the most easily recognised of the irregular forms of this difficult 
genus. It has a most important claim to the attention of the speculative geologist, 
for, like the liikodomus marks on the pillars of the temple of Serapis, I conceive 
that it affords evidence of a rising above and sinking beneath the level of the sea, 
of the lower tertiary beds of Alabama. Wherever we find a continuous deposit of 
fossil oyster-shells, wo recognise an ancient estuary, bay, or lagoon, cut off from 
the main ocean; for in no geological period were these bivalves ever colonized in 
the open sea, although they were liable to have been occasionally drifted there by 
currents. To present a clear view of the subject, I subjoin a section of the cliff at 
Claiborne, with a description, originally published in the Journal of the Academy 
of Natural Sciences of Philadelphia, in 1834, and in my work on tertiary fossils, in 
1835. The section is in the ascending order. 
45 feet. 
3 feet. 
17 feet. 
3 feet. 
70 feet. 
Level of the Alabama river, in the lowest stage of the water. 
L The inferior stratum is a dark-colored mixture of sand and clay, containing 
a group of shells, many of the species of which occur in the arenaceous deposit, 
No. 3 of the section. 
2. A dark-colored clay or marl, seventy feet in thickness, characterized by Os¬ 
trea sellaformis, generally of a small size, with disunited valves, and rather sparsely 
Right bank of Alabama river at Claiborne. 
Argillaceous limestone, 
indurated. 
Group of shells, similar to those of the Paris eocene, 
Ostrea sellEeformis, in indurated sand. 
Dark colored clay, with Ostrea sellajformis, 
Sand and clay, with oceanic shells, same as in No. 3. 
ated with a different group of fossils from any I had observed in Alabama. In Dr. Morton’s “ Synopsis of 
the Organic Remains of the Cretaceous Group,” the white limestone, in which this oyster shell occurs, 
was referred to the upper division of this group ; but further investigation of the fossils has satisfied 
me that they are of eocene origin. Two species of organic remains which occur in the limestone, (Scu¬ 
te Ha Lyelli and Pecten calvatus ,) I have obtained from the newest stratum at Claiborne, No. 4 of the 
section; but this Carolina limestone I believe to have been deposited in estuaries, like stratum No. 2, of 
the Claiborne section, with which it is doubtless of precisely the same geological age. Dr. Blanding, 
many years since, presented me specimens of Ostrea sellcrformis and Cardita Blandingi, which he found 
at Vance’s ferry* on the Santee river, and which enabled me to connect the formation of that locality 
with the eocene of Alabama. The following is a list of the fossils which I found in 1832, in the different 
localities of lower tertiary limestone in South-Carolina: Conus gyratus, Olivia carolinensis, Cyprsea 
lapidosa, Ostrea sellaeformis, Pecten calvatus, P. membranosus, Tenebratula lachryma, Balanus pere- 
grinus, Scutella Lyelli, Lunulites Lyelli* carolinensis, Echinus infulatus, Anthophyllum cuneifonnis. 
