, all strictly belonging to American forms; and it is obvious that a mountain, as it became slowly upheaved, would be colonised from the surrounding lowlands.
So it is with the inhabitants of lakes and marshes, excepting in so far as great facility of transport has allowed the same forms to prevail throughout large portions of the world.
We see the same principle in the character of most of the blind animals inhabiting the caves of America and of Europe.
Other analogous facts could be given.