that several of the islands possess their own species of the tortoise,
mocking-thrush, finches, and numerous plants, these species having the
same general habits, occupying analogous situations, and obviously
filling the same place in the natural economy of this archipelago, that
strikes me with wonder. It may be suspected that some of these
representative species, at least in the case of the tortoise and of
some of the birds, may hereafter prove to be only well-marked races;
but this would be of equally great interest to the philosophical
naturalist. I have said that most of the islands are in sight of each
other: I may specify that Charles Island is fifty miles from the
nearest part of Chatham Island, and thirty-three miles from the nearest
part of Albemarle Island. Chatham Island is sixty miles from the
nearest part of James Island, but there are two intermediate islands
between them which were not visited by me. James Island is only ten
miles from the nearest part of Albemarle Island, but the two points
where the collections were made are thirty-two miles apart. I must
repeat, that neither the nature of the soil, nor height of the land,
nor the climate, nor the general character of the associated beings,
and therefore their action one on another, can differ much in the
different islands. If there be any sensible difference in their
climates, it must be between the Windward group (namely, Charles and
Chatham Islands), and that to leeward; but there seems to be no
corresponding difference in the productions of these two halves of the
archipelago.
The only light which I can throw on this remarkable difference in the
inhabitants of the different islands, is, that very strong currents of
the sea running in a westerly and W.N.W. direction must separate, as
far as transportal by the sea is concerned, the southern islands from
the northern ones; and between these northern islands a strong N.W.
current was observed, which must effectually separate James and
Albemarle Islands. As the archipelago is free to a most remarkable
degree from gales of wind, neither the birds, insects, nor lighter
seeds, would be blown from island to island. And lastly, the profound
depth of the ocean between the islands, and their apparently recent (in
a geological sense) volcanic origin, render it highly unlikely that
they were ever united; and this, probably, is a far more important
consideration than any other, with respect to the geographical
distribution of their inhabitants. Reviewing the facts here given, one
is astonished at the amount of creative force, if such an expression
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