low perch. Therefore in these breeds, especially in
the two first, a considerable diminution in the wing-bones might have
been expected, but this is not the case. In every specimen, after
disarticulating and cleaning the bones, I carefully compared the
relative length of the two main bones of the wing to each other, and of
the two main bones of the leg to each other, with those of _G.
bankiva_; and it was surprising to see (except in the case of the
tarsi) how exactly the same relative length had been retained. This
fact is curious, from showing how truly the proportions of an organ may
be inherited, although not fully exercised during many generations. I
then compared in several breeds the {271} length of the femur and tibia
with the humerus and ulna, and likewise these same bones with those of
_G. bankiva_; the result was that the wing-bones in all the breeds
(except the Burmese Jumper, which has unnaturally short legs) are
slightly shortened relatively to the leg-bones; but the decrease is so
slight that it may be due to the standard specimen of _G. bankiva_
having accidentally had wings of slightly greater length than usual; so
that the measurements are not worth giving. But it deserves notice that
the Silk and Frizzled fowls, which are quite incapable of flight, had
their wings _less_ reduced relatively to their legs than in almost any
other breed! We have seen with domesticated pigeons that the bones of
the wings are somewhat reduced in length, whilst the primary feathers
are rather increased in length, and it is just possible, though not
probable, that in the Silk and Frizzled fowls any tendency to decrease
in the length of the wing-bones from disuse may have been checked
through the law of compensation, by the decreased growth of the
wing-feathers, and consequent increased supply of nutriment. The
wing-bones, however, in both these breeds, are found to be slightly
reduced in length when judged by the standard of the length of the
sternum or head, relatively to these same parts in _G. bankiva_.

The actual weight of the main bones of the leg and wing in twelve
breeds is given in the two first columns in the following table. The
calculated weight of the wing-bones relatively to the leg-bones, in
comparison with the leg and wing-bones of _G. bankiva_, are given in
the third column,--