s to prove that species arise
in a given way. Deductively, he desires to show that, if they arise in
that way, the facts of distribution, development, classification, &c.,
may be accounted for, _i.e._ may be deduced from their mode of origin,
combined with admitted changes in physical geography and climate, during
an indefinite period. And this explanation, or coincidence of observed
with deduced facts, is, so far as it extends, a verification of the
Darwinian view.

There is no fault to be found with Mr. Darwin's method, then; but it is
another question whether he has fulfilled all the conditions imposed by
that method. Is it satisfactorily proved, in fact, that species may be
originated by selection? that there is such a thing as natural
selection? that none of the phaenomena exhibited by species are
inconsistent with the origin of species in this way? If these questions
can be answered in the affirmative, Mr. Darwin's view steps out of the
ranks 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 with assuredly 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 artificial or natural. 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
even 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 their 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 inf