sterpiece. The
"Origin of Species" containing, in the idea of natural selection,
the distinctive contribution of Darwin to the theory of organic
evolution, was published in November, 1859. In only one brief
sentence did he there allude to man, but twelve years later he
published the "Descent of Man," in which the principles of the
earlier volume found their logical outcome. In other works Darwin
added vastly to our knowledge of coral reefs, organic variation,
earthworms, and the comparative expression of the emotions in man
and animals. Darwin died in ignorance of the work upon variation
done by his great contemporary, Gregor Mendel, whose work was
rediscovered in 1900. "Mendelism" necessitates much modification of
Darwin's work, which, however, remains the maker of the greatest
epoch in the study of life and the most important contribution to
that study ever made. Its immortal author died on April 19, 1882,
and was buried in Westminster Abbey.

_I.--Creation or Evolution?_

When on board H.M.S. Beagle as naturalist, I was much struck with
certain facts in the distribution of the organic beings inhabiting South
America, and in the geographical relations of the present to the past
inhabitants of that continent. These facts, as will be seen in the
latter chapters of this volume, seemed to throw some light on the origin
of species--that mystery of mysteries, as it has been called by one of
our greatest philosophers. On my return home, in 1837, it occurred to me
that something might perhaps be made out on this question by patiently
accumulating and reflecting on all sorts of facts which could possibly
have any bearing on it. After five years' work, I allowed myself to
speculate on the subject, and drew up some short notes; these I enlarged
in 1844 into a sketch of the conclusions which then seemed to me
probable. From that period to the present day I have steadily pursued
the same object. I hope that I may be excused for entering on these
personal details, as I give them to show that I have not been hasty in
coming to a decision.

In considering the origin of species, it is quite conceivable that a
naturalist, reflecting on the mutual affinities of organic beings, on
their embryological relations, their geographical distribution,
geological succession, and other such facts, might come to the
conclusion that species had not been independently cre