of age. In this treatise he inquires into the origin of compounds
and of minerals; also he conceived that all the rocks as well as all
chemical compounds and minerals originated from organic life. These
inquiries were reiterated in his "Memoirs on Physics and Natural
History," which appeared in 1797, when he was fifty-three years old.

The atmosphere of philosophic France, as well as of England and Germany
in the eighteenth century, was charged with inquiries into the origin of
things material, though more especially of things immaterial. It was a
period of energetic thinking. Whether Lamarck had read the works of
these philosophers or not we have no means of knowing. Buffon, we know,
was influenced by Leibnitz.

Did Buffon's guarded suggestions have no influence on the young Lamarck?
He enjoyed his friendship and patronage in early life, frequenting his
house, and was for a time the travelling companion of Buffon's son. It
should seem most natural that he would have been personally influenced
by his great predecessor, but we see no indubitable trace of such
influence in his writings. Lamarckism is not Buffonism. It comprises in
the main quite a different, more varied and comprehensive set of
factors.[158]

Was Lamarck influenced by the biological writings of Haller, Bonnet, or
by the philosophic views of Condillac, whose _Essai sur l'Origine des
Connaissances humaines_ appeared in 1786; or of Condorcet, whom he must
personally have known, and whose _Esquisse d'un Tableau historique des
Progres de l'Esprit humain_ was published in 1794?[159] In one case only
in Lamarck's works do we find reference to these thinkers.

Was Lamarck, as the result of his botanical studies from 1768 to 1793,
and being puzzled, as systematic botanists are, by the variations of the
more plastic species of plants, led to deny the fixity of species?

We have been unable to find any indications of a change of views in his
botanical writings, though his papers are prefaced by philosophical
reflections.

It would indeed be interesting to know what led Lamarck to change his
views. Without any explanation as to the reason from his own pen, we
are led to suppose that his studies on the invertebrates, his perception
of the gradations in the animal scale from monad to man, together with
his inherent propensity to inquire into the origin of things, also his
studies on fossils, as well as the broadening nature of his zooelogical
investigations and