he same thing. Hence a race-mark, if one is to be found,
must stand for, by co-existing with, the whole mass of properties that
form the inheritance. Can colour serve for a race-mark in this profound
sense? That is the only question here.

First of all, what is the use of being coloured one way or the other?
Does it make any difference? Is it something, like the heart-line of
the hand, that may go along with useful qualities, but in itself seems
to be a meaningless accident? Well, as some unfortunate people will
be able to tell you, colour is still a formidable handicap in the
struggle for existence. Not to consider the colour-prejudice in other
aspects, there is no gainsaying the part it plays in sexual selection
at this hour. The lower animals appear to be guided in the choice of
a mate by externals of a striking and obvious sort. And men and women
to this day marry more with their eyes than with their heads.

The coloration of man, however, though it may have come to subserve
the purposes of mating, does not seem in its origin to have been like
the bright coloration of the male bird. It was not something wholly
useless save as a means of sexual attraction, though in such a capacity
useful because a mark of vital vigour. Colour almost certainly
developed in strict relation to climate. Right away in the back ages
we must place what Bagehot has called the race-making epoch, when the
chief bodily differences, including differences of colour, arose
amongst men. In those days, we may suppose, natural selection acted
largely on the body, because mind had not yet become the prime condition
of survival. The rest is a question of pre-historic geography. Within
the tropics, the habitat of the man-like apes, and presumably of the
earliest men, a black skin protects against sunlight. A white skin,
on the other hand--though this is more doubtful--perhaps economizes
sun-heat in colder latitudes. Brown, yellow and the so-called red are
intermediate tints suitable to intermediate regions. It is not hard
to plot out in the pre-historic map of the world geographical provinces,
or "areas of characterization," where races of different shades
corresponding to differences in the climate might develop, in an
isolation more or less complete, such as must tend to reinforce the
process of differentiation.

Let it not be forgotten, however, that individual plasticity plays
its part too in the determination of human colour. The Anglo-Indian
p