The Descent of Man

apparently of Batrachians. Throughout the
enormous class of insects, as Kirby remarks,
"the law is that the male shall seek the female."
(18. Kirby and Spence, 'Introduction to Entomology,'
vol. iii. 1826, p. 342.) Two good authorities,
Mr. Blackwall and Mr. C. Spence Bate, tell
me that the males of spiders and crustaceans
are more active and more erratic in their habits
than the females. When the organs of sense or
locomotion are present in the one sex of insects
and crustaceans and absent in the other, or
when, as is frequently the case, they are more
highly developed in the one than in the other, it
is, as far as I can discover, almost invariably the
male which retains such organs, or has them
most developed; and this shews that the male is
the more active member in the courtship of the
sexes. (19. One parasitic Hymenopterous insect
(Westwood, 'Modern Class. of Insects,' vol. ii. p.
160) forms an exception to the rule, as the male
has rudimentary wings, and never quits the cell
in which it is born, whilst the female has well-