les moins armees, etc., ont deja disparu ou
disparaitront."

Erasmus Darwin (See Ernst Krause and Charles Darwin, "Erasmus Darwin",
London, 1879.) had a firm grip of the "idea of the gradual formation and
improvement of the Animal world," and he had his theory of the process.
No sentence is more characteristic than this: "All animals undergo
transformations which are in part produced by their own exertions, in
response to pleasures and pains, and many of these acquired forms or
propensities are transmitted to their posterity." This is Lamarckism
before Lamarck, as his grandson pointed out. His central idea is that
wants stimulate efforts and that these result in improvements, which
subsequent generations make better still. He realised something of the
struggle for existence and even pointed out that this advantageously
checks the rapid multiplication. "As Dr Krause points out, Darwin just
misses the connection between this struggle and the Survival of the
Fittest." (Osborn op. cit. page 142.)

Lamarck (1744-1829) (See E. Perrier "La Philosophie Zoologique avant
Darwin", Paris, 1884; A. de Quatrefages, "Darwin et ses Precurseurs
Francais", Paris, 1870; Packard op. cit.; also Claus, "Lamarck als
Begrunder der Descendenzlehre", Wien, 1888; Haeckel, "Natural History
of Creation", English translation London, 1879; Lang "Zur Charakteristik
der Forschungswege von Lamarck und Darwin", Jena, 1889.) seems to have
thought out his theory of evolution without any knowledge of Erasmus
Darwin's which it closely resembled. The central idea of his theory
was the cumulative inheritance of functional modifications. "Changes
in environment bring about changes in the habits of animals. Changes in
their wants necessarily bring about parallel changes in their habits. If
new wants become constant or very lasting, they form new habits, the new
habits involve the use of new parts, or a different use of old
parts, which results finally in the production of new organs and the
modification of old ones." He differed from Buffon in not attaching
importance, as far as animals are concerned, to the direct influence of
the environment, "for environment can effect no direct change whatever
upon the organisation of animals," but in regard to plants he agreed
with Buffon that external conditions directly moulded them.

Treviranus (1776-1837) (See Huxley's article "Evolution in Biology",
"Encyclopaedia Britannica" (9th edit.), 1878, pages 744-751, and Sul