ariations of instinct
in a state of nature will be strengthened by briefly considering a few
cases under domestication. We shall thus also be enabled to see the
respective parts which habit and the selection of {213} so-called
accidental variations have played in modifying the mental qualities of our
domestic animals. A number of curious and authentic instances could be
given of the inheritance of all shades of disposition and tastes, and
likewise of the oddest tricks, associated with certain frames of mind or
periods of time. But let us look to the familiar case of the several breeds
of dogs: it cannot be doubted that young pointers (I have myself seen a
striking instance) will sometimes point and even back other dogs the very
first time that they are taken out; retrieving is certainly in some degree
inherited by retrievers; and a tendency to run round, instead of at, a
flock of sheep, by shepherd-dogs. I cannot see that these actions,
performed without experience by the young, and in nearly the same manner by
each individual, performed with eager delight by each breed, and without
the end being known,--for the young pointer can no more know that he points
to aid his master, than the white butterfly knows why she lays her eggs on
the leaf of the cabbage,--I cannot see that these actions differ
essentially from true instincts. If we were to see one kind of wolf, when
young and without any training, as soon as it scented its prey, stand
motionless like a statue, and then slowly crawl forward with a peculiar
gait; and another kind of wolf rushing round, instead of at, a herd of
deer, and driving them to a distant point, we should assuredly call these
actions instinctive. Domestic instincts, as they may be called, are
certainly far less fixed or invariable than natural instincts; but they
have been acted on by far less rigorous selection, and have been
transmitted for an incomparably shorter period, under less fixed conditions
of life.

How strongly these domestic instincts, habits, and dispositions are
inherited, and how curiously they become mingled, is well shown when
different breeds of dogs are {214} crossed. Thus it is known that a cross
with a bull-dog has affected for many generations the courage and obstinacy
of greyhounds; and a cross with a greyhound has given to a whole family of
shepherd-dogs a tendency to hunt hares. These domestic instincts, when thus
tested by crossing, resemble natural instincts, which in a