3 
of bones collected there, is essentially the same with that 
which occupied the country on the advent of the whites. 
This remarkable fact, however, is reported by Professor 
Baird, that all the species represented in the collections made 
in the Carlisle cave, have degenerated in size, and this 
modern degeneracy ranges from ten to twenty-five per cent. 
The shell mounds on the Atlantic Coast north and south 
have been partially investigated by Professor Wyman, Pro- 
fessor Baird, and others. In these mounds human remains 
are constantly met with, but none which can serve as proof of 
ereat antiquity. Perhaps the best evidence that these shell 
mounds are of ancient date, is furnished by the facts report- 
ed by Professor Baird, that those of Maine contain the bones 
of the great Auk (Alca impennis) and those of the walrus. 
Of these the first is supposed to be entirely extinct, and both 
in modern times have been confined to higher latitudes. 
Tae mounds of the western states, the copper mines of 
Lake Superior, the old oil wells of Pennsylvania, and the 
lead mines of Kentucky, really afford us the only traces of 
human occupation yet found within our territory, which have 
a respectable antiquity, and one which can be measured even 
negatively in years. All these traces of the ancient seml1- 
civilized people that once inhabited the Mississippi. valley, 
are found overgrown by what we term the “ primeval forest,” 
in which are trees five hundred years old; and these trees in 
some instances, are growing on the prostrate trunks of indi- 
viduals of equal size, belonging to a preceding generation. 
This, then, is the record. We can positively assert that the 
works of the mound builders were abandoned and overgrown 
by forests a thousand years ago; how much before that time 
we have no means of knowing. We may fairly infer that 
some hundreds of years were consumed in the multiplication 
of this ancient people, in their spread over. and subjugation 
of the country they occupied, in the substitution of cultivated 
farms for the pre-existent forest, in the construction of towns 
so numerous as to thickly dot all the surface, in the thorough 
exploration and extensive working of the mineral districts 
and oil fields, in the acquisition of the degree of civilization 
