interesting contribution to science, irrespective of theory. In
domestication, this intercrossing may be prevented; and in this prevention
lies the art of producing varieties. But "the art itself is Nature," since
the whole art consists in allowing the most universal of all natural
tendencies in organic things (inheritance) to operate uncontrolled by other
and obviously incidental tendencies. No new power, no artificial force, is
brought into play either by separating the stock of a desirable variety so
as to prevent mixture, or by selecting for breeders those individuals which
most largely partake of the peculiarities for which the breed is valued.
{I-9]

We see everywhere around us the remarkable results which Nature may be said
to have brought about under artificial selection and separation. Could she
accomplish similar results when left to herself? Variations might begin, we
know they do begin, in a wild state. But would any of them be preserved and
carried to an equal degree of deviation? Is there anything in Nature which
in the long-run may answer to artificial selection? Mr. Darwin thinks that
there is; and Natural Selection is the key-note of his discourse,

As a preliminary, he has a short chapter to show that there is variation in
Nature, and therefore something for natural selection to act upon. He
readily shows that such mere variations as may be directly referred to
physical conditions (like the depauperation of plants in a sterile soil, or
their dwarfing as they approach an Alpine summit, the thicker fur of an
animal from far northward, etc.), and also those individual differences
which we everywhere recognize but do not pretend to account for, are not
separable by any assignable line from more strongly-marked varieties;
likewise that there is no clear demarkation between the latter and
sub-species, or varieties of the highest grade (distinguished from species
not by any known inconstancy, but by the supposed lower importance of their