The Descent of Man

ence that this purpose cannot be of a definite
nature. The horns do not shew marks of friction,
as if used for any ordinary work. Some
authors suppose (65. Kirby and Spence, 'Introduction
to Entomology,' vol. iii. P. 300.) that as
the males wander about much more than the
females, they require horns as a defence against
their enemies; but as the horns are often blunt,
they do not seem well adapted for defence. The
most obvious conjecture is that they are used
by the males for fighting together; but the males
have never been observed to fight; nor
could Mr. Bates, after a careful examination of
numerous species, find any sufficient evidence,
in their mutilated or broken condition, of their
having been thus used. If the males had been
habitual fighters, the size of their bodies would
probably have been increased through sexual
selection, so as to have exceeded that of the
females; but Mr. Bates, after comparing the two
sexes in above a hundred species of the Copridae,
did not find any marked difference in this