of their predecessors, by agencies similar to those
which at the present day produce varieties and races, and therefore in
an altogether natural way; and it is a probable, though not a necessary
consequence of this hypothesis, that all living beings have arisen from
a single stock. With respect to the origin of this primitive stock,
or stocks, the doctrine of the origin of species is obviously not
necessarily concerned. The transmutation hypothesis, for example, is
perfectly consistent either with the conception of a special creation of
the primitive germ, or with the supposition of its having arisen, as a
modification of inorganic matter, by natural causes.

The doctrine of special creation owes its existence very largely to the
supposed necessity of making science accord with the Hebrew cosmogony;
but it is curious to observe that, as the doctrine is at present
maintained by men of science, it is as hopelessly inconsistent with the
Hebrew view as any other hypothesis.

If there be any result which has come more clearly out of geological
investigation than another, it is, that the vast series of extinct
animals and plants is not divisible, as it was once supposed to be, into
distinct groups, separated by sharply-marked boundaries. There are no
great gulfs between epochs and formations--no successive periods marked
by the appearance of plants, of water animals, and of land animals,
en masse. Every year adds to the list of links between what the older
geologists supposed to be widely separated epochs: witness the crags
linking the drift with older tertiaries; the Maestricht beds linking the
tertiaries with the chalk; the St. Cassian beds exhibiting an abundant
fauna of mixed mesozoic and palaeozoic types, in rocks of an epoch once
supposed to be eminently poor in life; witness, lastly, the incessant
disputes as to whether a given stratum shall be reckoned devonian or
carboniferous, silurian or devonian, cambrian or silurian.

This truth is further illustrated in a most interesting manner by
the impartial and highly competent testimony of M. Pictet, from whose
calculations of what percentage of the genera of animals, existing in
any formation, lived during the preceding formation, it results that in
no case is the proportion less than 'one-third', or 33 per cent. It is
the triassic formation, or the commencement of the mesozoic epoch, which
has received the smallest inheritance from preceding ages. The other
formations