Species, mutability of, i. 78, 137;
law of introduction of, 96, 101-2;
extinction of, 98.
(See also Selection, natural)
Spencer, Herbert, birth of, i. 5;
and Evolution, 122, 123;
arguments with Huxley on Evolution, 123;
sends Darwin a copy of his Essays, 124;
suggests "survival of the fittest" as alternative to "natural selection," 125, 171;
Wallace's relations with, 125;
Darwin's approval of "survival of the fittest," 174;
autobiography of, ii. [211]
—— letters from:
on "Origin of the Races of Man," ii. [18];
on theory of flight, [27]-8;
on "Darwinism,"[47];
on Lord Salisbury's view of Natural Selection, [59], [60], [65];
on Land Nationalisation Society, [154];
on "Progress and Poverty," etc., [154]-5
Spilosoma menthastri, i. 179
Spiritualism, Wallace's belief in, ii. [122], [167], [178], [181] et seq., [239]-40;
Huxley on, [187];
Lord Avebury on, [212]
Spiritualists, Association of, ii. [198], [199]
Spontaneous generation, i. 274
Spruce, Mr., i. 150, 161, 166, 232
Stanley, Dean, at Linlathen, ii. [228]
Stephens' "Illustrations of British Insects," i. [23] (note)