Contributions to the Theory of Natural Selection

Sitta, sexual colouring and nidification of, 243 (#x7_x_7_i32).

Sittella, sexual colouring and nidification of, 243 (#x7_x_7_i32).

Snakes, mimicry among, 101 (#x3_x_3_i49).

Song of birds, instinctive or imitative, 220 (#x6_x_6_i48).

Species, law of population of, 28 (#x2_x_2_i14);

abundance or rarity of, dependent on the adaptation to conditions, 33 (#x2_x_2_i20);

definition of, 141 (#x4_x_4_i38), 161 (#x4_x_4_i57);

the range and constancy of, 143 (#x4_x_4_i41);

extreme variation in, 163 (#x5_x_5_i0), 164 (#x5_x_5_i1).

Speed of animals, limits of, 292 (#x8_x_8_i36).

Sphecia craboniforme, 90 (#x3_x_3_i34).

Sphecomorpha chalybea, 96 (#x3_x_3_i39).

Sphegidæ, mimicked by flies, 97 (#x3_x_3_i40).

Spiders, which mimic ants, 98 (#x3_x_3_i43);

and flower buds, 99 (#x3_x_3_i44).

Spilosoma menthastri, 88 (#x3_x_3_i30).

Stainton, Mr., on moths rejected by turkeys, 78 (#x3_x_3_i21), 88 (#x3_x_3_i30).

Stalachtis, a genus of Erycinidæ, the object of mimicry, 84 (#x3_x_3_i25).

Stinging insects generally conspicuously coloured, 72 (#x3_x_3_i9).

Streptocitta, 196 (#x6_x_6_i10).

Sturnidæ, sexual colouring and nidification of, 244 (#x7_x_7_i38).

Sturnopastor, 239 (#x7_x_7_i13).

St. Helena, 10 (#x1_x_1_i245).

Streptolabis hispoides, 93 (#x3_x_3_i36).

Struggle for existence, 28 (#x2_x_2_i14), 33 (#x2_x_2_i20).

Survival of the fittest, law of, stated, 33 (#x2_x_2_i20);

its action in determining colour, 67 (#x3_x_3_i2).

Swainson’s circular and quinarian theory, 45 (#x2_pgepubid00024).

Sylviadæ, sexual colouring and nidification of, 245 (#x7_x_7_i45).

Synapta, 258 (#x7_x_7_i76).

TACHORNIS phœnicobea, 228 (#x6_x_6_i71).

Tachyris hombronii, 172 (#x5_x_5_i18);

ithome, 172 (#x5_x_5_i18);

lycaste, 172 (#x5_x_5_i18);

lyncida, 172 (#x5_x_5_i18);

nephele, 172 (#x5_x_5_i18);

nero, 172 (#x5_x_5_i18);

zarinda, 172 (#x5_x_5_i18).

Tanagridæ, sexual colouring and nidification of, 245 (#x7_x_7_i45).

Tapir, 299 (#x8_x_8_i45).

Telephori, similar colouring of two sexes, 114 (#x4_x_4_i3).

Temperate and cold climates favourable to civilization, 318 (#x9_x_9_i26).

Thecodontia, 299 (#x8_x_8_i45).

Therates, mimicked by Heteromera, 95 (#x3_x_3_i37).

Thyca descombesi, 172 (#x5_x_5_i18);

hyparete, 172 (#x5_x_5_i18);

rosenbergii, 172 (#x5_x_5_i18);

zebuda, 172 (#x5_x_5_i18).

Tiger, adaptive colouring of, 52 (#x2_x_2_i51).

Times newspaper on Natural Selection, 296 (#x8_x_8_i39).