Each species may have had its origin in a single pair, or individual, where an individual was sufficient, and species may have been created in succession at such times and in such places as to enable them to multiply and endure for an appointed period, and occupy an appointed space on the globe.

Geology differs as widely from cosmogony, as speculations concerning the creation of man differ from history.

No tools have yet been met with in any of the gravels occurring at the higher levels of the valley of the Seine; but no importance can be attached to this negative fact, as so little search has yet been made for them.

I long ago suggested the hypothesis, that in the basin of the Thames there are indications of a meeting in the Pleistocene period of a northern and southern fauna.

Amidst the vicissitudes of the earth's surface, species cannot be immortal, but must perish, one after another, like the individuals which compose them. There is no possibility of escaping from this conclusion.

Such discoveries have led me, and other geologists, to reconsider the evidence previously derived from caves brought forward in proof of the high antiquity of Man.

The present is the key to the past