he rank of
hypotheses into those of proved theories; but, so long as the
evidence at present adduced falls short of enforcing that
affirmation, so long, to our minds, must the new doctrine be
content to remain among the former--an extremely valuable, and in
the highest degree probable, doctrine; indeed, the only extant
hypothesis which is worth anything in a scientific point of view;
but still a hypothesis, and not yet the theory of species.

"After much consideration, and assuredly with no bias against
Mr. Darwin's views, it is our clear conviction that, as the
evidence stands, it is not absolutely proven that a group of
animals having all the characters exhibited by species in nature,
has ever been originated by selection, whether natural or
artificial. Groups having the morphological character of species,
distinct and permanent races, in fact, have been so produced over
and over again; but there is no positive evidence at present that
any group of animals has, by variation and selective breeding,
given rise to another group which was in the least degree
infertile with the first. Mr. Darwin is perfectly aware of this
weak point, and brings forward a multitude of ingenious and
important arguments to diminish the force of the objection. We
admit the value of these arguments to the fullest extent; nay, we
will go so far as to express our belief that experiments,
conducted by a skilful physiologist, would very probably obtain
the desired production of mutually more or less infertile breeds
from a common stock in a comparatively few years; but still, as
the case stands at present, this little 'rift within the lute' is
not to be disguised or overlooked."--(_Westminster Review_,
1860.)

"We should leave a very wrong impression on the reader's mind if
we permitted him to suppose that the value of Darwin's work
depends wholly on the ultimate justification of the theoretical
views which it contains. On the contrary, if they were disproved
to-morrow, the book would still be the best of its kind--the most
compendious statement of well-sifted facts bearing on the
doctrine of species that has ever appeared. The chapters on
variation, on the struggle for existence, on instinct, on
hybridism, on the imperfection of the geological record, on
g