me classes of Chinese, the feet of young
girls have been bound in such a way as to produce a small, malformed foot,
but this has not resulted in any hereditary diminution in the size of the
feet of Chinese females. Many other similar mutilations have been
practised, as for example, the flattening of the skull of some North
American Indians, but the deformity must be produced again with each
recurring generation. One after another, the cases that were supposed to
give positive evidence have been reinvestigated, with the result that has
been stated above. It would seem, therefore, that heredity and congenital
modification must play by far the greater part in the evolution of
species.

* * * * *

The doctrine of natural selection took form in the mind of Darwin mainly
on account of three potent influences; these were, first, the geological
doctrine of uniformitarianism proposed by Lyell, second, his own
observations of wild life in many lands and his analysis of the breeder's
results with domesticated animals, and third, the writings of Malthus
dealing with overpopulation. As Darwin had read the works of Buffon,
Lamarck, and Erasmus Darwin, his grandfather, who had written a famous
treatise under the title of "Zoonomia," he was familiar with the evidences
known in his student days tending to prove that organic evolution was a
real natural process. Lyell's doctrine of uniform geological history made
an early and deep impression upon his mind, and it led him to ask himself
whether the efficient causes of past evolution might not be revealed by an
analysis of the present workings of nature. As naturalist of the "Beagle"
during its four years' cruise around the world, Darwin saw many new lands
and observed varied circumstances under which the organisms of the tropics
and other regions lived their lives. The fierce struggle for existence
waged by the denizens of the jungle recalled to him the views of Malthus
regarding overpopulation and its results. These and other influences led
him to begin the remarkable series of note-books, from which it is
interesting indeed to learn how the doctrine of natural selection began to
assume a definite and permanent form in his mind, as year followed year,
and evidence was added to evidence. And it is a valuable lesson to the
student of science that for twenty-five years Darwin devoted all his time
to the acquisition of facts before he gave his doctrine to the w