analogy between the different parts of the same plant which seemed to
repeat themselves: unity and evolution were revealed to him at once.

Three years later the sight of a half-broken sheep-skull, which he found
by chance on the sand of the Venetian Lido, taught him that the same
law, as he had suspected, applied also to vertebrate animals, and that
the skull might be considered as a series of strongly modified vertebrae.
He had, in fact, already hinted at the principle, shortly after put
forward by Lamarck, and long afterward developed and firmly established
by Darwin. He considered the difference in the anatomical structure of
animal species as modifications of a type or planned structure,
modifications brought about by the difference of life, food, and
dwellings. He had discovered as early as 1786 the intermaxillary bone in
man, i.e., the remnant of a part which had had to be adapted to the
exigencies of the changed structure; and proved thereby that there had
been a primitive similarity of structure, which had been transformed by
development of some parts and atrophy of others. Goethe's sketch of an
_Introduction into Comparative Anatomy_, which he wrote in 1795, urged
by A. von Humboldt, has remained, if I may believe those competent to
judge, a fundamental stone of modern science. And I may be allowed, as I
am unversed in such matters, to invoke the authority of one of the most
eminent living physiologists, Helmholtz, who says of Goethe's anatomical
essay, that in it the poet "teaches, with the greatest clearness and
decision, that all differences in the structure of animal species are to
be considered as changes of one fundamental type, which have been
brought about by fusion, transformation, aggrandizement, diminution, or
total annihilation of several parts. This has, indeed, become, in the
present state of comparative anatomy, the leading idea of this science.
It has never since been expressed better or more clearly than by Goethe:
and after-times have made few essential modifications."[59]

Now, the same may be said, I am told, in spite of some differences as to
details, of his metamorphosis of plants. I do not mean by this to say
that Goethe is the real author of the theory of evolution. There is
between him and Mr. Darwin the difference which there is between Vico
and Niebuhr, Herder and F.A. Wolf. In the one case we have a fertile
hint, in the other a well-established system, worked out by proofs and
con