its origin because of the
imagined benefit conferred, is the general procedure of the followers
of the Darwinian school." "Personal conviction, mere possibility,"
writes Quatrefages, "are offered as proofs, or at least as arguments
in favor of the theory." "The realms of fancy are boundless," is
Blanchard's significant comment on Darwin's explanation of the
blindness of the mole. "On this class of speculation," says Bateson in
his "Materials for the Study of Variation," referring to Darwinian
speculation as to the beneficial or detrimental nature of variations,
"on this class of speculation the only limitations are those of the
ingenuity of the author." The general form of Darwin's argument,
declared the writer of a celebrated article in the North British
Review, is as follows: "All these things may have been, therefore my
theory is possible; and since my theory is a possible one, all those
hypotheses which it requires are rendered probable."

3. We pass now to the question of the possibility of building up a new
species by the accumulation of chance individual variations. That
species ever originate in this way is denied by the advocates of the
evolutionary theory which is now superseding Darwinism. Typical of the
new school is the botanist Hugo De Vries of Amsterdam. The
"first-steps" in the origin of new species according to De Vries are
not fluctuating individual variations, but mutations, i.e., definite
and permanent modifications. According to the mutation theory a new
species arises from the parent species, not gradually but suddenly. It
appears suddenly "without visible preparation and without transitional
steps." The wide acceptance with which this theory is meeting must be
attributed to the fact that men of science no longer believe in the
origin of species by the accumulation of slight fluctuating
modifications. To quote the words of De Vries, "Fluctuating variation
cannot overstep the limits of the species, even after the most
prolonged selection--still less can it lead to the production of new,
permanent characters." It has been the wont of Darwinians to base their
speculations on the assumption that "an inconceivably long time" could
effect almost anything in the matter of specific transformations. But
the evidence which has been amassed during the past forty years leaves
no doubt that there is a limit to individual variability which neither
time nor skill avail to remove. As M. Blanchard asserts in his w