GEOLOGICAL SOCIETY OF LONDON. 
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lengtli give place to sandy plains and low islands skirting the 
coast, in whichj strata, containing marine shells of recent species, 
are met with, slightly elevated above the sea. Occasionally de- 
posits formed in freshwater swamps occur, below the mean level 
of the Atlantic or overflowed at high tide. In this district Mr. 
Nuttall discovered, on the Neuse 15 miles below Newburn, in 
South Carolina, a large assemblage of mammalian bones, inclu- 
ding those of the Mastodon giganteum, resting on a deposit con- 
taining 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 species, but considers it as 
agreeing with the horse-tooth brought by Mr. Darwin from the 
north side of the Plata in Entre Hios 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 into the soft boggy ground. 
Georgia. — -Bones of the Mastodon and Megatherium occur in 
this district in swamps formed upon a marine sand containing 
shells of species now inhabiting the neighbouring sea. 
Mr. Lyell in conclusion offers the following observations : — 
1. That the extinct animals of Bigbone Lick and those of the 
Atlantic border in the Carolinas and in Georgia belonging to 
the same group, the identical species of Mastodon and elephant 
being in both cases associated 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 freshwater, accompanying the bones of Masto- 
dons, agree with species of Mollusca now inhabiting the same 
regions. 
3. Under similar circumstances Mr. Darwin found the Masto- 
don and horse in Entre Rios, near the Plata, and the Megath- 
