Most persons imagine that the arguments in favour of it are
overwhelming; but to some few minds, and these, it must be 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 carcass 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