ness and size
the parent Arab stock, so that the latter, by the regulations for the
Goodwood Races, are favoured in the weights they carry. Lord Spencer and
others have shown how the cattle of England have increased in weight
and in early maturity, compared with the stock formerly kept in this
country. By comparing the accounts given in old pigeon treatises of
carriers and tumblers with these breeds as now existing in Britain,
India, and Persia, we can, I think, clearly trace the stages through
which they have insensibly passed, and come to differ so greatly from
the rock-pigeon.

Youatt gives an excellent illustration of the effects of a course of
selection, which may be considered as unconsciously followed, in so far
that the breeders could never have expected or even have wished to have
produced the result which ensued--namely, the production of two distinct
strains. The two flocks of Leicester sheep kept by Mr. Buckley and Mr.
Burgess, as Mr. Youatt remarks, "have been purely bred from the original
stock of Mr. Bakewell for upwards of fifty years. There is not a
suspicion existing in the mind of any one at all acquainted with
the subject that the owner of either of them has deviated in any one
instance from the pure blood of Mr. Bakewell's flock, and yet the
difference between the sheep possessed by these two gentlemen is so
great that they have the appearance of being quite different varieties."

If there exist savages so barbarous as never to think of the inherited
character of the offspring of their domestic animals, yet any one animal
particularly useful to them, for any special purpose, would be carefully
preserved during famines and other accidents, to which savages are
so liable, and such choice animals would thus generally leave more
offspring than the inferior ones; so that in this case there would be a
kind of unconscious selection going on. We see the value set on animals
even by the barbarians of Tierra del Fuego, by their killing and
devouring their old women, in times of dearth, as of less value than
their dogs.

In plants the same gradual process of improvement, through the
occasional preservation of the best individuals, whether or not
sufficiently distinct to be ranked at their first appearance as distinct
varieties, and whether or not two or more species or races have become
blended together by crossing, may plainly be recognised in the increased
size and beauty which we now see in the varieties