acknowledgment, and I think Mr. Romanes has not sufficiently
distinguished between "useless characters" and "useless specific
distinctions." On referring to all the passages indicated by him I find
that, in regard to specific characters, Mr. Darwin is very cautious in
admitting inutility. His most pronounced "admissions" on this question
are the following: "But when, from the nature of the organism and of the
conditions, modifications have been induced which are unimportant for
the welfare of the species, they may be, and apparently often have been,
transmitted in nearly the same state _to numerous, otherwise modified,
descendants_" (_Origin_, p. 175). The words I have here italicised
clearly show that such characters are usually not "specific," in the
sense that they are such as distinguish species from each other, but are
found in numerous allied species. Again: "Thus a large yet undefined
extension may safely be given to the direct and indirect results of
natural selection; but I now admit, after reading the essay of Naegeli on
plants, and the remarks by various authors with respect to animals, more
especially those recently made by Professor Broca, that in the earlier
editions of my _Origin of Species_ I perhaps attributed too much to the
action of natural selection or the survival of the fittest. I have
altered the fifth edition of the _Origin_ so as to confine my remarks to
adaptive changes of structure, _but I am convinced, from the light
gained during even the last few years, that very many structures which
now appear to us useless, will hereafter be proved to be useful, and
will therefore come within the range of natural selection_. Nevertheless
I did not formerly consider sufficiently the existence of structures
which, _as far as we can at present judge_, are neither beneficial nor
injurious; and this I believe to be one of the greatest oversights as
yet detected in my work." Now it is to be remarked that neither in these
passages nor in any of the other less distinct expressions of opinion on
this question, does Darwin ever admit that "specific characters"--that
is, the particular characters which serve to distinguish one species
from another--are ever useless, much less that "a large proportion of
them" are so, as Mr. Romanes makes him "freely acknowledge." On the
other hand, in the passage which I have italicised he strongly expresses
his view that much of what we suppose to be useless is due to our
ignorance