other formations not uncommonly exhibit 60, 80, or even 94 per cent. of
genera in common with those whose remains are imbedded in their
predecessor. Not only is this true, but the subdivisions of each
formation exhibit new species characteristic of, and found only in,
them; and, in many cases, as in the lias for example, the separate beds
of these subdivisions are distinguished by well-marked and peculiar
forms of life. A section, a hundred feet thick, will exhibit, at
different heights, a dozen species of ammonite, none of which passes
beyond its particular zone of limestone, or clay, into the zone below it
or into that above it; so that those who adopt the doctrine of special
creation must be prepared to admit, that at intervals of time,
corresponding with the thickness of these beds, the Creator thought fit
to interfere with the natural course of events for the purpose of
making a new ammonite. It is not easy to transplant oneself into the
frame of mind of those who can accept such a conclusion as this, on any
evidence short of absolute demonstration; and it is difficult to see
what is to be gained by so doing, since, as we have said, it is obvious
that such a view of the origin of living beings is utterly opposed to
the Hebrew cosmogony. Deserving no aid from the powerful arm of
Bibliolatry, then, does the received form of the hypothesis of special
creation derive any support from science or sound logic? Assuredly not
much. The arguments brought forward in its favour all take one form:
If species were not supernaturally created, we cannot understand the
facts 'x' or 'y', or 'z'; we cannot understand the structure of animals
or plants, unless we suppose they were contrived for special ends; we
cannot understand the structure of the eye, except by supposing it to
have been made to see with; we cannot understand instincts, unless we
suppose animals to have been miraculously endowed with them.

As a question of dialectics, it must be admitted that this sort of