like manner
become curiously blended together, and for a long period exhibit traces of
the instincts of either parent: for example, Le Roy describes a dog, whose
great-grandfather was a wolf, and this dog showed a trace of its wild
parentage only in one way, by not coming in a straight line to his master
when called.

Domestic instincts are sometimes spoken of as actions which have become
inherited solely from long-continued and compulsory habit, but this, I
think, is not true. No one would ever have thought of teaching, or probably
could have taught, the tumbler-pigeon to tumble,--an action which, as I
have witnessed, is performed by young birds, that have never seen a pigeon
tumble. We may believe that some one pigeon showed a slight tendency to
this strange habit, and that the long-continued selection of the best
individuals in successive generations made tumblers what they now are; and
near Glasgow there are house-tumblers, as I hear from Mr. Brent, which
cannot fly eighteen inches high without going head over heels. It may be
doubted whether any one would have thought of training a dog to point, had
not some one dog naturally shown a tendency in this line; and this is known
occasionally to happen, as I once saw in a pure terrier: the act of
pointing is probably, as many have thought, only the exaggerated pause of
an animal preparing to spring on its prey. When the first tendency to point
was once displayed, methodical selection and the inherited effects of
compulsory training in each successive generation would soon complete the
{215} work; and unconscious selection is still at work, as each man tries
to procure, without intending to improve the breed, dogs which will stand
and hunt best. On the other hand, habit alone in some cases has sufficed;
no animal is more difficult to tame than the young of the wild rabbit;
scarcely any animal is tamer than the young of the tame rabbit; but I do
not suppose that domestic rabbits have ever been selected for tameness; and
I presume that we must attribute the whole of the inherited change from
extreme wildness to extreme tameness, simply to habit and long-continued
close confinement.

Natural instincts are lost under domestication: a remarkable instance of
this is seen in those breeds of fowls which very rarely or never become
"broody," that is, never wish to sit on their eggs. Familiarity alone
prevents our seeing how universally and largely the minds of our domestic
anima