Nothing is easier than to admit in words the truth of the universal struggle for life, or more difficult, at least I have found it so, than constantly to bear this conclusion in mind.

When on board H.M.S. 'Beagle,' as naturalist, I was much struck with certain facts in the distribution of the inhabitants of South America.

It has been a bitter mortification for me to digest the conclusion that the 'race is for the strong' and that I shall probably do little more but be content to admire the strides others made in science.

Did man, after his first inroad into South America, destroy, as has been suggested, the unwieldy Megatherium and the other Edentata?

Such simple instincts as bees making a beehive could be sufficient to overthrow my whole theory.

The great variability of all the external differences between the races of man, likewise indicates that they cannot be of much importance; for if important, they would long ago have been either fixed and preserved, or eliminated.