another
set of
workers of
a
different
size and
structure;—a
graduated
series
having
been first
formed, as
in the
case of
the driver
ant, and
then the
extreme
forms,
from being
the most
useful to
the
community,
having
been
produced
in greater
and
greater
numbers
through
the
natural
selection
of the
parents
which
generated
them;
until none
with an
intermediate
structure
were
produced.
Thus, as I
believe,
the
wonderful
