GEOLOGY. 57 
bottom with its multitude of shells, which remained just as they 
had died in their holes, reminded him of an ancient raised sea- 
bottom at Hopedale, Labrador. 
These clay beds graduated into clay and sand, containing a fer- 
ruginous layer, supposed by Dr. Shepard, Jr., to be the horizon of 
the phosphate beds. These beds correspond to the beds of clay 
at Gardiner, Maine, where Sir Charles Lyell discovered the bones 
of the Bison and Walrus. They contain bones of the Megalonyx, 
Mastodon, Elephant, Tapir, two species of Horse, Peccary, Rhi- 
noceros and Manatee. The sands graduate into the beach sands 
of the close of the Quaternary, just as do. the Bison and Walrus 
beds of the Kennebec river. The phosphate beds, then, were 
probably rolled masses of Eocene rock crowded with shells, min- 
gled with the bones of the animals above mentioned, deposited 
and arranged by the waves of a shallow sea a few feet deep. This 
sea was much shallower even than that which covered the ancient 
sea bottom beneath, which must have been only from one to five 
or ten fathoms deep, as the same shells are at the present day 
thrown up on the neighboring beaches in great abundance, and he 
had dredged some of them at a depth of from five to thirty feet at 
Beaufort, N. C. 
After their deposition, the carbonate of lime of the shell marl 
of the Eocene rocks had been replaced by phosphate of lime. 
How this had been effected, and whence the phosphate of lime was 
derived, was a question still unsettled by chemists. He alluded 
to the theory of Prof. Shaler that this phosphate deposit had been 
formed at the bottom of the Gulf Stream, which, according to 
that geologist, had probably flowed over the site of the present 
phosphate beds; and in opposing the theory suggested that the 
_ phosphate beds were deposited in shallow water, perhaps lagoons 
as suggested by Prof. Holmes, as they rested in a shallow water 
deposit above alluded to. There was no apparent evidence, as 
well shown by the facts published by Tuomey in his geological 
survey of South Carolina, of a depression of the coast. On the 
other hand there is no apparent evidence of glacial action on 
` the coast, since the Quaternary sands are marine or aerial, and 
Tuomey states that he has nowhere in the state of South Carolina 
seen any angular blocks, nor a pebble a foot in diameter. More- 
over, the life of the Quaternary in this state indicated even a 
warmer climate than at present obtains. 
Since these remarks were made, he had met by. accident with 
