tamorphosis originated
in the course of one generation, the animals with extremities would have an
advantage over the rest, which ought to show itself in the natural
selection; but if the development of an extremity needs 10,000 generations,
the individual in which the process of the development begins produces
1/10000 of the extremity and the advantage, resulting therefrom is reduced
to zero. For an organ can only be of advantage when it performs its
functions; and on {106} the first of the 10,000 stages of development the
extremity can not perform its functions. Just think of the cetacea! Of the
hind extremity, only its carrier, the pelvis, has been developed; and even
this is only represented by the two hip-bones, hanging in the flesh. As to
the python, the hind extremities are more complete, but they lie hidden
under the skin, and therefore are of no use for local movement. Such
examples show that in the history of the development of an organ thousands
of years may pass, and numerous generations may arise and disappear, until
it reaches that grade of perfection where it is of use to its owner. How
therefore, can we look upon such an organ, when finally it is perfect, as a
product of selection in the sense of Darwin?"

We find the scientific objections to the selection theory collected in
detail in the before-mentioned works of Wigand, Blanchard, His, von Baer,
and especially in Mivart's "Genesis of Species," (London, MacMillan, 1871);
and it is a praiseworthy testimony of Darwin's love of truth, that lately
he himself, the originator of the selection theory, willingly admits these
weak points in his theory,[7] while Haeckel and many of his followers {107}
in Germany still stoutly reject every doubt of the autocracy of the
selection principle.

In summing up all we have said thus far about the theories of descent, of
evolution, and of selection, we still find all three solutions of the
scientific problems to be hypotheses, but hypotheses of very different
value. The idea of descent has the most scientific ground; it will, as a
permanent presupposition, govern all scientific investigations as to the
origin of species, even if it does not exclude the idea of an
often-repeated primitive generation of organisms--especially of those that
stand still lower in development. More uncertain and less comprehensive is
the position of the evolution theory; in all likelihood, the idea of an
origin through development will have to