intellect. I therefore no doubt overlook a few smaller points in which
Natural Selection may still act on men and brutes alike. Colour is one of
them, and I have alluded to this in correlation to constitution, in an
abstract I have made at Sclater's request for the "Natural History Review."
(406*/2. "Nat. Hist. Review," 1864, page 328.) At the same time, there is
so much evidence of migrations and displacements of races of man, and so
many cases of peoples of distinct physical characters inhabiting the same
or similar regions, and also of races of uniform physical characters
inhabiting widely dissimilar regions,--that the external characteristics of
the chief races of man must, I think, be older than his present
geographical distribution, and the modifications produced by correlation to
favourable variations of constitution be only a secondary cause of external
modification. I hope you may get the returns from the Army. (406*/3.
Measurements taken of more than one million soldiers in the United States
showed that "local influences of some kind act directly on structure."--
"Descent of Man," 1901, page 45.) They would be very interesting, but I do
not expect the results would be favourable to your view.

With regard to the constant battles of savages leading to selection of
physical superiority, I think it would be very imperfect and subject to so
many exceptions and irregularities that it would produce no definite
result. For instance: the strongest and bravest men would lead, and
expose themselves most, and would therefore be most subject to wounds and
death. And the physical energy which led to any one tribe delighting in
war, might lead to its extermination, by inducing quarrels with all
surrounding tribes and leading them to combine against it. Again, superior
cunning, stealth, and swiftness of foot, or even better weapons, would
often lead to victory as well as mere physical strength. Moreover, this
kind of more or less perpetual war goes on amongst savage peoples. It
could lead, therefore, to no differential characters, but merely to the