物種起源（英文全本）全文TXT下載-(英)達爾文-線上免費下載

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