xture of species, as in mules.

Of these ten factors or principles, and other views of Dr. Darwin, some
are similar to those of Lamarck, while others are directly opposed.
There are therefore no good grounds for supposing that Lamarck was
indebted to Darwin for his views. Thus Erasmus Darwin supposes that the
formation of organs precedes their use. As he says, "The lungs must be
previously formed before their exertions to obtain fresh air can exist;
the throat or oesophagus must be formed previous to the sensation or
appetites of hunger and thirst" (_Zoonomia_, p. 222). Again (_Zoonomia_,
i., p. 498), "From hence I conclude that with the acquisition of new
parts, new sensations and new desires, as well as new powers, are
produced" (p. 226). Lamarck does not carry his doctrine of
use-inheritance so far as Erasmus Darwin, who claimed, what some still
maintain at the present day, that the offspring reproduces "the effects
produced upon the parent by accident or cultivation."

The idea that all animals have descended from a similar living filament
is expressed in a more modern and scientific way by Lamarck, who derived
them from monads.

The Erasmus Darwin way of stating that the transformations of animals
are in part produced by their own exertions in consequence of their
desires and aversions, etc., is stated in a quite different way by
Lamarck.

Finally the principle of law of battle, or the combat between the males
for the possession of the females, with the result "that the strongest
and most active animal should propagate the species," is not hinted at
by Lamarck. This view, on the contrary, is one of the fundamental
principles of the doctrine of natural selection, and was made use of by
Charles Darwin and others. So also Erasmus anticipated Charles Darwin in
the third great want of "security," in seeking which the forms and
colors of animals have been modified. This is an anticipation of the
principle of protective mimicry, so much discussed in these days by
Darwin, Wallace, and others, and which was not even mentioned by
Lamarck. From the internal evidence of Lamarck's writings we therefore
infer that he was in no way indebted to Erasmus Darwin for any hints or
ideas.[157]

FOOTNOTES:

[152] Vol. ii., 3d edition. Our references are to this edition.

[153] Krause, _The Scientific Works of Erasmus Darwin_, footnote on
p. 134: "See 'Athenaeum,' March, 1875, p. 423."

[154] _Zoonomia_, i., p. 505 (3d edition