orms. This
assertion, as we shall see in the next chapter, is certainly erroneous.
As Sir J. Lubbock has remarked, "Every species is a link between other
allied forms." If we take a genus having a score of species, recent
and extinct, and destroy four-fifths of them, no one doubts that the
remainder will stand much more distinct from each other. If the extreme
forms in the genus happen to have been thus destroyed, the genus itself
will stand more distinct from other allied genera. What geological
research has not revealed, is the former existence of infinitely
numerous gradations, as fine as existing varieties, connecting together
nearly all existing and extinct species. But this ought not to be
expected; yet this has been repeatedly advanced as a most serious
objection against my views.
It may be worth while to sum up the foregoing remarks on the causes
of the imperfection of the geological record under an imaginary
illustration. The Malay Archipelago is about the size of Europe from
the North Cape to the Mediterranean, and from Britain to Russia; and
therefore equals all the geological formations which have been examined
with any accuracy, excepting those of the United States of America. I
fully agree with Mr. Godwin-Austen, that the present condition of the
Malay Archipelago, with its numerous large islands separated by wide and
shallow seas, probably represents the former state of Europe, while most
of our formations were accumulating. The Malay Archipelago is one of
the richest regions in organic beings; yet if all the species were to
be collected which have ever lived there, how imperfectly would they
represent the natural history of the world!
But we have every reason to believe that the terrestrial productions of
the archipelago would be preserved in an extremely imperfect manner in
the formations which we suppose to be there accumulating. Not many
of the strictly littoral animals, or of those which lived on naked
submarine rocks, would be embedded; and those embedded in gravel or
sand would not endure to a distant epoch. Wherever sediment did not
accumulate on the bed of the sea, or where it did not accumulate at a
sufficient rate to protect organic bodies from decay, no remains could
be preserved.
Formations rich in fossils of many kinds, and of thickness sufficient to
last to an age as distant in futurity as the secondary formations lie
in the past, would generally be formed in the archipelago only duri
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