On this doctrine of the extermination of an infinitude of connecting
links, between the living and extinct inhabitants of the world, and at
each successive period between the extinct and still older species, why
is not every geological formation charged with such links? Why does not
every collection of fossil remains afford plain evidence of the
gradation and mutation of the forms of life? We meet with no such
evidence, and this is the most obvious and forcible of the many
objections which may be urged against my theory. Why, again, do whole
groups of allied species appear, though certainly they often falsely
appear, to have come in suddenly on the several geological stages? Why
do we not find great piles of strata beneath the Silurian system,
stored with the remains of the progenitors of the Silurian groups of
fossils? For certainly on my theory such
strata must somewhere have been deposited at these ancient and utterly
unknown epochs in the world s history.
I can answer these questions and grave objections only on the
supposition that the geological record is far more imperfect than most
geologists believe. It cannot be objected that there has not been time
sufficient for any amount of organic change; for the lapse of time has
been so great as to be utterly inappreciable by the human intellect.
The number of specimens in all our museums is absolutely as nothing
compared with the countless generations of countless species which
certainly have existed. We should not be able to recognise a species as
the parent of any one or more species if we were to examine them ever
so closely, unless we likewise possessed many of the intermediate links
between their past or parent and present states; and these many links
we could hardly ever expect to discover, owing to the imperfection of
the geological record. Numerous existing doubtful forms could be named
which are probably varieties; but who will pretend that in future ages
so many fossil links will be discovered, that naturalists will be able
to decide, on the common view, whether or not these doubtful forms are
varieties? As long as most of the links between any two species are
unknown, if any one link or intermediate variety be discovered, it will
simply be classed as another and distinct species. Only a small portion
of the world has been geologically explored. Only organic beings of
certain classes can be preserved in a fossil condition, at least in any
great number. Widely ranging species vary most, and varieties are often
at first local, both causes rendering the discovery of intermediate
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