hat of
habits on the condition of the parts and even on that of the
organization, each animal may receive in its parts and its
organization, modifications susceptible of becoming very
considerable, and of giving rise to the condition in which we find
all animals.

"To maintain that this second conclusion is unfounded, it is
necessary at first to prove that each point of the surface of the
globe never varies in its nature, its aspect, its situation whether
elevated or depressed, its climate, etc., etc.; and likewise to
prove that any part of animals does not undergo, even at the end of
a long period, any modification by changes of circumstances, and by
the necessity which directs them to another kind of life and action
than that which is habitual to them.

"Moreover, if a single fact shows that an animal for a long time
under domestication differs from the wild form from which it has
descended, and if in such a species in domesticity we find a great
difference in conformation between the individuals submitted to
such habits and those restricted to different habits, then it will
be certain that the first conclusion does not conform to the laws of
nature, and that, on the contrary, the second is perfectly in accord
with them.

"Everything combines then to prove my assertion--namely, that it is
not the form, either of the body or of its parts, which gives rise
to habits, and to the mode of life among animals; but that it is on
the contrary the habits, the manner of living, and all the other
influencing circumstances which have, after a time, constituted the
form of the body and of the parts of animals. With the new forms,
new faculties have been acquired, and gradually nature has come to
form the animals as we actually see them.

"Can there be in natural history a consideration more important, and
to which we should give more attention, than that which I have just
stated?

"We will end this first part with the principles and the exposition
of the natural classification of animals."

In the fourth chapter of the third part (vol. ii. pp. 276-301) Lamarck
treats of the internal feelings of certain animals, which provoke wants
(_besoins_). This is the subject which has elicited so much adverse
criticism and ridicule, and has in many cases led to the wholesale
rejection of all of Lamarck's views. It is generally assumed or stated
by Lamarck's critics, w