confessed, intellects of no small power and grasp of knowledge, they have
not brought conviction. Among these minds, that of the famous naturalist
Lamarck, who possessed a greater acquaintance with the lower forms of life
than any man of his day, Cuvier not excepted, and was a good botanist to
boot, occupies a prominent place.

Two facts appear to have strongly affected the course of thought of this
remarkable man--the one, that finer or stronger links of affinity connect
all living beings with one another, and that thus the highest creature
grades by multitudinous steps into the lowest; the other, that an organ may
be developed in particular directions by exerting itself in particular
ways, and that modifications once induced may be transmitted and become
hereditary. Putting these facts together, Lamarck endeavoured to account
for the first by the operation of the second. Place an animal in new
circumstances, says he, and its needs will be altered; the new needs will
create new desires, and the attempt to gratify such desires will result in
an appropriate modification of the organs exerted. Make a man a blacksmith,
and his brachial muscles will develop in accordance with the demands made
upon them, and in like manner, says Lamarck, "the efforts of some
short-necked bird to catch fish without wetting himself have, with time and
perseverance, given rise to all our herons and long-necked waders."

The Lamarckian hypothesis has long since been justly condemned, and it is
the established practice for every tyro to raise his heel against the
carcase of the dead lion. But it is rarely either wise or instructive to
treat even the errors of a really great man with mere ridicule, and in the
present case the logical form of the doctrine stands on a very different
footing from its substance.

If species have really arisen by the operation of natural conditions, we