Chap. XI. 
SUMMAEY ON INSECTS. 
421 
Sexual selection implies that the more attractive 
individuals are preferred by the opposite sex ; and as 
with insects, when the sexes differ, it is the male which, 
with rare exceptions, is the most ornamented and 
departs most from the type to which the species 
belongs ; — and as it is the male which searches eagerly 
for the female, we must suppose that the females habit- 
ually or occasionally prefer the more beautiful males, 
and that these have thus acquired their beauty. That 
in most or all the orders the females have the power 
of rejecting any particular male, we may safely infer 
from the many singular contrivances possessed by the 
males, such as great jaws, adhesive cushions, spines, 
elongated legs, &c., for seizing the female ; for these 
contrivances shew that there is some difficulty in the 
act. In the case of unions between distinct species, 
of which many instances have been recorded, the 
female must have been a consenting party. Judging 
from what we know of the perceptive powers and 
affections of various insects, there is no antecedent im- 
probability in sexual selection having come largely into 
action ; but we have as yet no direct evidence on this 
head, and some facts are opposed to the belief, Never- 
theless, when we see many males pursuing the same 
female, we can hardly believe that the pairing is left to 
blind chance— that the female exerts no choice, and 
is not influenced by the gorgeous colours or other 
ornaments, with which the male alone is decorated. 
If we admit that the females of the Homoptera and 
Orthoptera appreciate the musical tones emitted by their 
male partners, and that the various instruments for this 
purpose have been perfected through sexual selection, 
there is little improbability in the females of other 
insects appreciating beauty in form or colour, and con- 
sequently in such characters having been thus gained 
