erous forms of life much closer together, it does not yield
the infinitely many fine gradations between past and present species
required on the theory, and this is the most obvious of the many
objections which may be urged against it. Why, again, do whole groups
of allied species appear, though this appearance is often false, to have
come in suddenly on the successive geological stages? Although we
now know that organic beings appeared on this globe, at a period
incalculably remote, long before the lowest bed of the Cambrian system
was deposited, why do we not find beneath this system great piles
of strata stored with the remains of the progenitors of the Cambrian
fossils? For on the theory, such strata must somewhere have been
deposited at these ancient and utterly unknown epochs of the world's
history.

I can answer these questions and objections only on the supposition
that the geological record is far more imperfect than most geologists
believe. The number of specimens in all our museums is absolutely as
nothing compared with the countless generations of countless species
which have certainly existed. The parent form of any two or more species
would not be in all its characters directly intermediate between
its modified offspring, any more than the rock-pigeon is directly
intermediate in crop and tail between its descendants, the pouter and
fantail pigeons. We should not be able to recognise a species as the
parent of another and modified species, if we were to examine the two
ever so closely, unless we possessed most of the intermediate links;
and owing to the imperfection of the geological record, we have no just
right to expect to find so many links. If two or three, or even more
linking forms were discovered, they would simply be ranked by many
naturalists as so many new species, more especially if found in
different geological substages, let their differences be ever so slight.
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 whether
or not these doubtful forms ought to be called varieties? 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. Many species when once formed never undergo any
further change but become extinct without leaving mod