elapsed between the extinction of the
Maestricht animals and the introduction of the Eocene tribes, or during
the Eocene epoch, or the rise may have been going on throughout one, or
several, or all of these periods.

It would be a purely gratuitous assumption to say that the inclined
cretaceous strata (_b_, fig. 11) on the flanks of the Pyrenees, were the
very last which were deposited during the Cretaceous period, or that, as
soon as they were upheaved, all or nearly all the species of animals and
plants now found fossil in them were suddenly exterminated; yet, unless
this can be affirmed, we cannot say that the Pyrenees were not upheaved
during the Cretaceous period. Consequently, another range of mountains,
at the base of which cretaceous rocks may lie in horizontal
stratification, may have been elevated, like the chain A, fig. 12,
during some part of the same great period.

There are mountains in Sicily two or three thousand feet high, the tops
of which are composed of limestone, in which a large proportion of the
fossil shells agree specifically with those now inhabiting the
Mediterranean. Here, as in many other countries, the deposits now in
progress in the sea must inclose shells and other fossils specifically
identical with those of the rocks constituting the contiguous land. So
there are islands in the Pacific where a mass of dead coral has emerged
to a considerable altitude, while other portions of the mass remain
beneath the sea, still increasing by the growth of living zoophytes and
shells. The chalk of the Pyrenees, therefore, may at a remote period
have been raised to an elevation of several thousand feet, while the
species found fossil in the same chalk still continued to be represented
in the fauna of the neighboring ocean. In a word, we cannot assume that
the origin of a new range of mountains caused the Cretaceous period to
cease, and served as the prelude to a new order of things in the animate
creation.

To illustrate the grave objections above advanced, against the theory
considered in the present chapter, let us suppose, that in some country
three styles of architecture had prevailed in succession, each for a
period of one thousand years; first the Greek, then the Roman, and then
the Gothic; and that a tremendous earthquake was known to have occurred
in the same district during one of the three periods--a convulsion of
such violence as to have levelled to the ground all the buildings then
standi