They believe that very many structures have been created for beauty in
the eyes of man, or for mere variety. This doctrine, if true, would be
absolutely fatal to my theory--yet I fully admit that many structures
are of no direct use to their possessor."

And after sundry illustrations and qualifications, he concludes (p.
200):--

"Hence every detail of structure in every living creature (making some
little allowance for the direct action of physical conditions) may be
viewed either as having been of special use to some ancestral form, or
as being now of special use to the descendants of this form--either
directly, or indirectly, through the complex laws of growth."

But it is one thing to say, Darwinically, that every detail observed in
an animal's structure is of use to it, or has been of use to its
ancestors; and quite another to affirm, teleologically, that every
detail of an animal's structure has been created for its benefit. On
the former hypothesis, for example, the teeth of the foetal Balaena
have a meaning; on the latter, none. So far as we are aware, there is
not a phrase in the 'Origin of Species', inconsistent with Professor
Kolliker's position, that "varieties arise irrespectively of the notion
of purpose, or of utility, according to general laws of Nature, and may
be either useful, or hurtful, or indifferent."

On the contrary, Mr. Darwin writes (Summary of Chap. V.):--

"Our ignorance of the laws of variation is profound. Not in one case
out of a hundred can we pretend to assign any reason why this or that
part varies more or less from the same part in the parents.... The