The Descent of Man

fe. This fact shews that in the Amphipoda, an
order low in the scale, the males and females
recognise each other, and are mutually attached.
The mental powers of the Crustacea are probably
higher than at first sight appears probable.
Any one who tries to catch one of the shorecrabs,
so common on tropical coasts, will perceive
how wary and alert they are. There is a
large crab (Birgus latro), found on coral islands,
which makes a thick bed of the picked fibres of
the cocoa-nut, at the bottom of a deep burrow.
It feeds on the fallen fruit of this tree by tearing
off the husk, fibre by fibre; and it always begins
at that end where the three eye-like depressions
are situated. It then breaks through one of these
eyes by hammering with its heavy front pincers,
and turning round, extracts the albuminous
core with its narrow posterior pincers. But
these actions are probably instinctive, so that
they would be performed as well by a young