Fossil Remains of the Mastodon, §c. 323 
Atlantic border.—Between the Appalachian Mountains and the At- 
lantic there is a wide extent 0} nearly horizontal tertiary strata, which 
at the base of the mountains are five hundred feet and upwards in height, 
but decline in level nearer the ocean, and at length give place to sandy 
Plains and low islands skirting the coast, in which strata containing ma- 
rine shells of recent species are met with, slightly elevated above the 
sea. Occasionally deposits formed in fresh-water swamps occur, below 
the mean level of the Atlantic or overflowed at high tide. In this district 
Mr. Nuttall discovered, on the Neuse fifteen miles below Newbern, in 
North Carolina, a large assemblage of mammalian bones, including 
those of the Mastodon giganteum, resting on a deposit containing marine 
shells of recent species. Mr.Conrad presented Mr. Lyell with the tooth 
of a horse covered with barnacles, from this locality. Professor Owen 
has examined it and could find no corresponding tooth of a recent spe- 
cies, but considers it as agreeing with the horse-tooth brought by Mr. 
Darwin from the north side of the Plata in Entre Rios, in South America. 
South Carolina.—Remains of the Mastodon were found in digging 
the Santee Canal, in a spot where large quadrupeds might now sink in- 
to the soft boggy ground. 
Georgia.—Bones of the Mastodon and Megatherium occur in this dis- 
trict in swamps formed upon a marine sand containing shells of species 
_ now inhabiting the neighboring sea. 
Mr. Lyell in conclusion offers the following observations :— 
1. That the extinct animals of Bigbone Lick and those of the Atlan- 
tic border in the Carolinas and in Georgia belong to the same group, 
the identical species of Mastodon and elephant being in both cases asso- 
ciated with the horse, and while we have the Mylodon and Megatherium 
in Georgia, the Megalonyx is stated by several authors to have been 
found at Bigbone Lick. 
2. On both sides of the Appalachian chain, the fossil shells, whether 
land or fresh-water, accompanying the bones of Mastodons, agree with 
Species of Mollusca now inhabiting the same regions. 
3. Under similar circumstances Mr. Darwin found the Mastodon and 
horse in Entre Rios, near the Plata, and the Megatherium, Megalonyx 
and Mylodon, together with the horse, in Bahia Blanca in Patagonia ; 
these South American remains being shown by their geological position 
to be of later date than certain marine newer pliocene, and post-pliocene 
Strata. Mr. Darwin also ascertained that some extinct animals of the 
same group are more modern in Patagonia than the drift with erratics. 
4. The extinct quadrupeds before alluded to in the United States liv- 
ed after the deposition of the northern drift, and consequently the cold- 
“hess of climate which probably coincided in date with the transportation 
of the drift, was not as some pretend the cause of their extinction. 
