on the Geological Survey of South Carolina. 71 



which are now unquestionably found in the eocene tertiary of 

 South Carolina, we see no reason to doubt the conclusion that 

 Mr. Tuomey came to in regard to the Ammonites placenta, found 

 by him at Wilmington, notwithstanding the fact that no Ammo- 

 nite had previously been found either in the tertiary of this coun- 

 try or in that of Europe. If one species survived the change, 

 many might, and probably did. 



Pliocene. — Scattered over the state, at various localities, par- 

 ticularly in Darlington and Sumter districts, are marl deposits of 

 an age later than the eocene, and which, following Mr. LyelPs 

 classification, Mr. Tuomey includes in the pliocene; as they are 

 found to contain a much greater proportion of recent shells than 

 the rniocene beds of Virginia and Maryland. In the districts 

 named, the pliocene rests immediately on the cretaceous marls. 



Fossils of these beds. 



Mammalia. — Mastodon, Cervus. 



Pisces. — Carcharodon. Galeocerdo. Saurocephalus. 



Lamna. Hemipristis. Caelorhynchus. 



Mollusca. — Brachiopoda, 1 species. 



Gasteropoda, 78 " of which 39 are recent. 



Lamellibranchiata, 109 " " 47 * * 



Also of Cirripedia, 2 species, of which 1 is recent. 



Post-pliocene. — The post-pliocene deposits of South Carolina 

 occupy the line of the coast for about ten miles inland, rest- 

 nig upon the pliocene in Horby and Georgetown districts, and 

 south of this upon the eocene rocks. They are composed of 

 beds of sand, clay and mud, their whole thickness being about 

 sixty feet. 



Mammalia. — Mr. Tuomey found some fragments of bones in 

 the post-pliocene, which he concluded to belong to the Mega- 

 therium. 



Pisces. — Carcharias, Lamna. 



Myliobates, Diodon. 



Trichiurus. 

 Mollusca. — Pteropoda, 1 species. 



Gasteropoda, 39 



Lamellibranchiata, 65 



Also of Cirripedia, 1 species, Echinodermata 4 species, and 



Polyparia 2 species. 



Alluvium.— This in turn is noticed, and the question consider- 

 ed here whether the southern coast is subsiding as has been al- 

 leged. Our author concludes that it is not, and shows the evi- 

 dence brought in favor of such a view to be due to other causes. 



