I was so much impressed with these facts that I strongly insisted, in 1839 and 1845, on this "law of the succession of types,"--on "this wonderful relationship in the same continent between the dead and the living.

" Professor Owen has subsequently extended the same generalisation to the mammals of the Old World.

We see the same law in this author's restorations of the extinct and gigantic birds of New Zealand.

We see it also in the birds of the caves of Brazil.