nty-five years ago this doctrine had been subjected to a reductio ad
absurdum with classic clearness in Wigand's great work.

It is certainly a very peculiar phenomenon; for decades we behold a
doctrine reverently re-echoed; thoughtful investigators expose its
folly, but still the worship continues, the Zeitgeist must have its
idol. It appears, however, as if the Zeitgeist were gradually tiring of
its golden calf and were on the point of casting it into the
rubbish-heap. Misgivings arise on all sides; here one class of
objections are considered, there another. A closer examination reveals
that these are by no means new reasons, based on new researches, but
the very oldest, urged long ago and perhaps much more clearly and
forcibly. At that time, however, the Zeitgeist was under the spell of
the suggestion of individual men: it heard and saw nothing but the
captivating, obvious simplicity of the doctrine; but now when the
subject begins to be tedious and the discussion lags, the interest
consequently abates and the Zeitgeist suddenly grasps the old
objections, presented in a new garb, and what was hitherto truth, clear
and irrefutable, now sinks into the dreary, gray mists of myth. Sic
transit gloria mundi!

This has been the history of Darwinism, and especially of Darwin's
theory of sexual selection. What Grottewitz urges against it, was
advanced decades ago by other and more eminent men; then people would
not listen, to-day they are inclined to listen. Of very special
interest is the further admission, that "the principle of gradual
development" has been "considerably shaken" and is "certainly
untenable." Grottewitz points out that it has been demonstrated that
the progeny of the same parents are often entirely dissimilar, and that
new organs very suddenly spring up in individuals even when they had
had no previous existence. "A slight variation from the parent form is
of no utility to the progeny; they must acquire at once a completely
developed, new character, if it is to be of any use to them." Quite
right! but this one admission is destructive of the entire doctrine of
natural selection. If one accepts saltatory evolution, as for instance,
Heer, Koelliker, and Wigand did long ago, then, as Grottewitz now
discovers, the difficulty arising for Darwinism from the absence of the
numerous intermediary forms which it postulates, naturally disappears.

Grottewitz attributes sudden variation to the influence of environmen