s, &c., and colours of all
kinds, may be seen in purely-bred and closely related Dorking fowls, whilst
other points, such as the general form of body, and the presence of an
additional toe, have been attended to, and are invariably present. It has
also been ascertained that colour can be fixed in this breed, as well as in
any other.[585]

* * * * *

During the formation or improvement of a breed, its members will always be
found to vary much in those characters to which especial attention is
directed, and of which each slight improvement is eagerly sought and
selected. Thus with short-faced tumbler-pigeons, the shortness of the beak,
shape of head and plumage,--with carriers, the length of the beak and
wattle,--with fantails, the tail and carriage,--with Spanish fowls, the
white face and comb,--with long-eared rabbits, the length of ear, are all
points which are eminently variable. So it is in every case, and the large
price paid for first-rate animals proves the difficulty of breeding them up
to the highest standard of excellence. This subject has been discussed by
fanciers,[586] and the greater prizes given for highly improved breeds, in
comparison with those given for old breeds which are not now undergoing
rapid improvement, has been fully justified. Nathusius makes[587] a similar
remark when discussing the less uniform character of improved Shorthorn
cattle and of the English horse, in comparison, for example, with the
unennobled cattle of Hungary, or with the horses of the Asiatic steppes.
This want of uniformity in the parts which at the time are undergoing
selection, chiefly depends on the strength of the principle of reversion
but it likewise depends to a certain extent on the continued {239}
variability of the parts which have recently varied. That the same parts do
continue varying in the same manner we must admit, for, if it were not so,
there could be no improvement beyond an early standard of excellence, and
we know that such improvement is not only possible, but is of general
occurrence.

As a consequence of continued variability, and more especially of
reversion, all highly improved races, if neglected or not subjected to
incessant selection, soon degenerate. Youatt gives a curious instance of
this in some cattle formerly kept in Glamorganshire; but in this case the
cattle were not fed with sufficient care. Mr. Baker, in his memoir on the
Horse, sums up: "It must have bee