regard to the inhabitants of islands, is their
affinity to those of the nearest mainland, without being actually the
same species. Numerous instances could be given of this fact. I will
give only one, that of the Galapagos Archipelago, situated under the
equator, between 500 and 600 miles from the shores of South America.
Here almost every product of the land and water bears the unmistakeable
stamp of the American continent. There are twenty-six land birds,
and twenty-five of these are ranked by Mr. Gould as distinct species,
supposed to have been created here; yet the close affinity of most of
these birds to American species in every character, in their habits,
gestures, and tones of voice, was manifest. So it is with the other
animals, and with nearly all the plants, as shown by Dr. Hooker in
his admirable memoir on the Flora of this archipelago. The naturalist,
looking at the inhabitants of these volcanic islands in the Pacific,
distant several hundred miles from the continent, yet feels that he is
standing on American land. Why should this be so? why should the species
which are supposed to have been created in the Galapagos Archipelago,
and nowhere else, bear so plain a stamp of affinity to those created in
America? There is nothing in the conditions of life, in the geological
nature of the islands, in their height or climate, or in the proportions
in which the several classes are associated together, which resembles
closely the conditions of the South American coast: in fact there is
a considerable dissimilarity in all these respects. On the other hand,
there is a considerable degree of resemblance in the volcanic nature
of the soil, in climate, height, and size of the islands, between
the Galapagos and Cape de Verde Archipelagos: but what an entire and
absolute difference in their inhabitants! The inhabitants of the Cape
de Verde Islands are related to those of Africa, like those of the
Galapagos to America. I believe this grand fact can receive no sort of
explanation on the ordinary view of independent creation; whereas on the
view here maintained, it is obvious that the Galapagos Islands would be
likely to receive colonists, whether by occasional means of transport or
by formerly continuous land, from America; and the Cape de Verde
Islands from Africa; and that such colonists would be liable to
modification;--the principle of inheritance still betraying their
original birthplace.

Many analogous facts could be