the terms
"water-population," "air-population," and "land-population" are
understood in the senses here defined, natural science has nothing to
say in favour of the proposition that they succeeded one another in
the order given by Mr. Gladstone; but that, on the contrary, all the
evidence we possess goes to prove that they did not. Whence it will
follow that, if Mr. Gladstone has interpreted Genesis rightly (on which
point I am most anxious to be understood to offer no opinion), that
interpretation is wholly irreconcilable with the conclusions at present
accepted by the interpreters of nature--with everything that can be
called "a demonstrated conclusion and established fact" of natural
science. And be it observed that I am not here dealing with a question
of speculation, but with a question of fact.

Either the geological record is sufficiently complete to afford us
a means of determining the order in which animals have made their
appearance on the globe or it is not. If it is, the determination of
that order is little more than a mere matter of observation; if it is
not, then natural science neither affirms nor refutes the "fourfold
order," but is simply silent.

The series of the fossiliferous deposits, which contain the remains of
the animals which have lived on the earth in past ages of its history,
and which can alone afford the evidence required by natural science of
the order of appearance of their different species, may be grouped in
the manner shown in the left-hand column of the following table, the
oldest being at the bottom:--

Formations First known appearance of
Quaternary.
Pliocene.
Miocene.
Eocene. Vertebrate _air_-population (Bats).
Cretaceous.
Jurassic. Vertebrate _air_-population (Birds and
Pterodactyles).
Triassic.
Upper Palaeozoic.
Middle Palaeozoic. Vertebrate _land_-population (Amphibia,
Reptilia [?]).
Lower Palaeozoic.
Silurian. Vertebrate _water_-population (Fishes).
Invertebrate _air_ and _land_-
population (Flying Insects and Scorpions).
Cambrian. Invertebrate _water_-population (much
earlier, if _Eozoon_ is animal).

In the right-hand column I have noted the group of strata in which,
according to our present information, the _land, air,_ and _