As before, the treatment must be illustrative; we cannot work through the list.

Further, we must be content with a very rough division into bodily and mental features.

Just at this point we shall find it very hard to say what is to be reckoned bodily and what mental.

Leaving these niceties to the philosophers, however, let us go ahead as best we can.
Oh for an external race-mark about which there could be no mistake! That has always been a dream of the anthropologist; but it is a dream that shows no signs of coming true.

All sorts of tests of this kind have been suggested.