s, Archangels,
Breasts, Shields, and others in Europe, and many others in India. It would
indeed be as puerile to suppose that all these birds are descended from so
many distinct wild stocks as to suppose this to be the case with the many
varieties of the gooseberry, heartsease, or dahlia. Yet these pigeons all
breed true, and many of them present sub-varieties which likewise truly
transmit their character. They differ greatly from each other and from the
rock-pigeon in plumage, slightly in size and proportions of body, in size
of feet, and in the length and thickness of their beaks. They differ from
each other in these respects more than do dovecot-pigeons. Although we may
safely admit that the latter, which vary slightly, and that the
toy-pigeons, which vary in a greater degree in accordance with their more
highly-domesticated condition, are descended from _C. livia_, including
under this name the above-enumerated wild geographical races; yet the
question becomes far more difficult when we consider the eleven principal
races, most of which have been so profoundly modified. It can, however, be
shown, by indirect evidence of a perfectly conclusive nature, that these
principal races are not descended from so many wild stocks; and if this be
once admitted, few will dispute that they are the descendants of _C.
livia_, which agrees with them so closely in habits and in most characters,
which varies in a state of nature, and which has certainly {188} undergone
a considerable amount of variation, as in the toy-pigeons. We shall
moreover presently see how eminently favourable circumstances have been for
a great amount of modification in the more carefully tended breeds.

The reasons for concluding that the several principal races have not
descended from so many aboriginal and unknown stocks may be grouped under
the following six heads:--_Firstly_, if the eleven chief races have not
arisen from the variation of some one species, together with its
geographical races, they must be descended from several extremely distinct
aboriginal species; for no amount of crossing between only six or seven
wild forms could produce races so distinct as pouters, carriers, runts,
fantails, turbits, short-faced tumblers, jacobins, and trumpeters. How
could crossing produce, for instance, a pouter or a fantail, unless the two
supposed aboriginal parents possessed the remarkable characters of these
breeds? I am aware that some naturalists, following P