164 
THE GEOLOGIST. 
the country surrounding the locality in which the bones were 
found. The portion described is that part of the sea-coast of 
Georgia which lies between the Alatamaha and Turtle rivers in 
one direction, and the Atlantic Ocean and the head of tide 
water on the other. For twenty miles inland the land is low, 
averaging a height of from ten to twenty feet, and reaching, in 
some instances, forty feet, and consisting of swamps, salt-marshes, 
sandy land, and clay loam. It then suddenly rises to the height 
of seventy feet, and runs back west at this elevation about twenty 
miles, at which point there is a similar elevation of between 
sixty and seventy feet. The whole of this district is a post- 
tertiaiy formation, and is composed of recent alluvium, and a 
well- characterized marine post-pliocene deposit. The recent 
alluvium is divided into inland-swamp, tide-swamp, and salt- 
marsh. The two last occupy a shallow basin, having a depth of 
about two feet, the bottom and sides of which are the post- 
pliocene formation. This the author divides into three groups, 
in the last of which, constituting the elevated sand hills, no or- 
ganic remains have been found ; in the tvfo former marine shells 
of existing species occur. 
The fossil bones of the land mammalia discovered by Mr. 
Cooper, were found resting on the yellow sand and enveloped in 
the recent clay alluvium. Their unworn state and the grouping 
together of many bones of the same skeleton, render it highly 
probable that the carcases of the animals falling or floating into 
a former lake or stream, sank to the sandy bottom, and were 
gradually covered to their present depth by the sedimentary de- 
posits from the water. Among them were remains of the Me- 
gatherium, Mastodon giganteum, mammoth, hippopotamus and 
horse. The fossil shells found in the post-pliocene, were species 
at present existing on the neighbouring shores. 
The facts narrated by Mr. Cooper lead to the following con- 
clusions : — 1st. That the post-pliocene formation extends fur- 
ther south than ]\Iaryland, to which it has hitherto been limited. 
