animals upon the globe, we have seen an advance in both cases, from
simple to higher forms of organization. In the botanical department
we have first sea, afterwards land plants; and amongst these the
simpler (cellular and cryptogamic) before the more complex. In the
department of zoology, we see, first, traces all but certain of
infusoria [shelled animalculæ]; then polypiaria, crinoidea, and
some humble forms of the articulata and mollusca; afterwards higher
forms of the mollusca; and it appears that these existed for ages
before there were any higher types of being. The first step forward
gives fishes, the humblest class of the vertebrata; and, moreover,
the earliest fishes partake of the character of the lower
sub-kingdom, the articulata. Afterwards come land animals, of which
the first are reptiles, universally allowed to be the type next in
advance from fishes, and to be connected with these by the links of
an insensible gradation. From reptiles we advance to birds, and
thence to mammalia, which are commenced by marsupialia,
acknowledgedly low forms in their class. That there is thus a
progress of some kind, the most superficial glance at the
geological history is sufficient to convince us."

Now this appears plausible and conclusive, but the correctness of the
recapitulation here made, and its conformity to actual nature, have been
sharply disputed. It may be true that sea plants came first, but of this
there is no proof; and of land plants there is not a shadow of evidence
that the simpler forms came into being before the more complex: the
simple and complex forms are found together in the more ancient _flora_.
It is true that we first see polypiaria, crinoidea, articulata, and
mollusca, but not exactly in the order stated by the author. It is true
that the next step gives us fishes, but it is not true that the earliest
fishes link on to the lower sub-kingdom, the articulata. It is true that