uppose that use-inheritance
especially affects the eight breeds that have varied most in size. If we
exclude these, there is only a total shortening of 7 per cent. to be
accounted for.

[36] _Variation of Animals and Plants under Domestication_, i. 183, 186.

[37] _Variation of Animals and Plants under Domestication_, i. 130, 135;
ii. 288.

[38] _Encyclopaedia Britannica_, article "Zoology."

[39] _Variation of Animals and Plants under Domestication_, ii. 367.

[40] _Variation of Animals and Plants under Domestication_, ii. 367. Why
then does the cheetah inherit ancestral habits so inadequately that it
is useless for the chase unless it has first learned to hunt for itself
before being captured? (ii. 133).

[41] _Descent of Man_, p. 33.

[42] _Origin of Species_, pp. 210, 211.

[43] E. S. Delamer on _Pigeons and Rabbits_, pp. 132, 103. For other
points referred to, see pages 133, 102, 100, 95, 131.

[44] _Origin of Species_, pp. 188, 110; _Descent of Man_, pp. 32-35;
_Variation of Animals and Plants under Domestication_, ii. 289, 293. Use
or disuse during lifetime of course co-operates, and in some cases, as
in that of the canoe Indians, may be the principal or even perhaps the
_sole_ cause of the change.

[45] For the importance of panmixia as invalidating Darwin's strongest
evidence for use-inheritance--namely, that drawn from the effects of
disuse in highly-fed domestic animals where there is supposed to be no
economy of growth--see Professor Romanes on Panmixia, _Nature_, April 3,
1890.

[46] _Descent of Man_, p. 33.

[47] _Descent of Man_, p. 33.

[48] _Variation of Animals and Plants under Domestication_, i., 453.

[49] _Descent of Man_, p. 33.

[50] _Descent of Man_, p. 33.

[51] Wallace shows that the changes in our domestic animals, if spread
over the thousands of years since the animals were first tamed, must be
extremely insignificant in each generation, and he concludes that such
infinitesimal effects of use and disuse would be swallowed up by the far
greater effects of variation and selection (_Darwinism_, p. 436).
Professor Romanes has replied to him in the _Contemporary Review_
(August 1889), showing that this is no disproof of the existence of the
minor factor, inasmuch as slight changes in each generation need not
necessarily be matters of life and death to the individual, although
their cumulative development by use-inheritance might eventually become
of much service. But selection