imself in these fields of thought,
and one so inflexible and unyielding in holding to an opinion once
formed as he, must have arrived at such views only after long
reflection. There is also every reason to suppose that Lamarck's theory
of descent was conceived by himself alone, from the evidence which lay
before him in the plants and animals he had so well studied for the
preceding thirty years, and that his inspiration came directly from
nature and not from Buffon, and least of all from the writings of
Erasmus Darwin.

FOOTNOTES:

[158] See the comparative summary of the views of the founders of
evolution at the end of Chapter XVII.

[159] While Rousseau was living at Montmorency "his thought wandered
confusedly round the notion of a treatise to be called 'Sensitive
Morality or the Materialism of the Age,' the object of which was to
examine the influence of external agencies, such as light, darkness,
sound, seasons, food, noise, silence, motion, rest, on our corporeal
machine, and thus, indirectly, upon the soul also."--_Rousseau_, by John
Morley (p. 164).

[160] Butler's _Evolution, Old and New_ (p. 244), and Isidore Geoffroy
St. Hilaire's _Histoire naturelle generale_, tome ii., p. 404 (1859).

[161] After looking in vain through both volumes of the _Recherches_ for
some expression of Lamarck's earlier views, I found a mention of it in
Osborn's _From the Greeks to Darwin_, p. 152, and reference to Huxley's
_Evolution in Biology_, 1878 ("Darwiniana," p. 210), where the
paragraphs translated above are quoted in the original.

CHAPTER XVI

THE STEPS IN THE DEVELOPMENT OF LAMARCK'S VIEWS ON EVOLUTION BEFORE THE
PUBLICATION OF HIS _PHILOSOPHIE ZOOLOGIQUE_

I. _From the Systeme des Animaux sans Vertebres_ (1801).

The first occasion on which, so far as his published writings show,
Lamarck expressed his evolutional views was in the opening lecture[162]
of his course on the invertebrate animals delivered in the spring of
1800, and published in 1801 as a preface to his _Systeme des Animaux
sans Vertebres_, this being the first sketch or prodromus of his later
great work on the invertebrate animals. In the preface of this book,
referring to the opening lecture, he says: "I have glanced at some
important and philosophic views that the nature and limits of this work
do not permit me to develop, but which I propose to take up elsewhere
with the details necessary to show on what facts they are based, and
with