beings. The form of a crystal is determined solely by the molecular
forces, and it is not surprising that dissimilar substances should
sometimes assume the same form; but with organic beings we should bear
in mind that the form of each depends on an infinity of complex
relations, namely on variations, due to causes far too intricate to be
followed, on the nature of the variations preserved, these depending on
the physical conditions, and still more on the surrounding organisms
which compete with each, and lastly, on inheritance (in itself a
fluctuating element) from innumerable progenitors, all of which have
had their forms determined through equally complex relations. It
appears incredible that the modified descendants of two organisms, if
these differed from each other in a marked manner, should ever
afterwards converge so closely as to lead to a near approach to
identity throughout their whole organisation. In the case of the
convergent races of pigs above referred to, evidence of their descent
from two primitive stocks is, according to von Nathusius, still plainly
retained, in certain bones of their skulls. If the races of man had
descended, as is supposed by some naturalists, from two or more
species, which differed from each other as much, or nearly as much, as
does the orang from the gorilla, it can hardly be doubted that marked
differences in the structure of certain bones would still be
discoverable in man as he now exists.
Although the existing races of man differ in many respects, as in
colour, hair, shape of skull, proportions of the body, etc., yet if
their whole structure be taken into consideration they are found to
resemble each other closely in a multitude of points. Many of these are
of so unimportant or of so singular a nature, that it is extremely
improbable that they should have been independently acquired by
aboriginally distinct species or races. The same remark holds good with
equal or greater force with respect to the numerous points of mental
similarity between the most distinct races of man. The American
aborigines, Negroes and Europeans are as different from each other in
mind as any three races that can be named; yet I was incessantly
struck, whilst living with the Fuegians on board the Beagle, with the
many little traits of character, shewing how similar their minds were
to ours; and so it was with a full-blooded negro with whom I happened
once to be intimate.
He who will read Mr. Tylor s and Sir J. Lubbock s interesting works
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