;
indirectly intermediate, 24, 135

Fossils, Silurian, not those which first existed in the world, 26, 138;
falling into or between existing groups and indirectly intermediate,
24, 137;
conditions favourable to preservation, not favourable to existence
of much life, 25, 139, 141

Fruit, attractive to animals, 130

Galapagos Islands and Darwin's views, xiv;
physical character of in relation to fauna, 31 _n._, 159

Galapagos Islands, fauna, 31 _n._, 82

Gasteropods, embryology, 218

Genera, crosses between, 11, 97;
wide ranging, has wide ranging species, 155;
origin of, 209

Geography, in relation to geology, 31 _n._, 174, 177

Geographical distribution, _see_ Distribution

Geology, as producing changed conditions, 4;
evidence from, 22, 133;
"destroys geography," 31 _n._

Glacial period, effect of on distribution of alpine and arctic plants,
165

Habit in relation to instinct, 17, 113, 115, 116

Habits in animals taught by parent, 18

Heredity, _see_ Inheritance

Homology of limbs, 38, 214

Homology, serial, 39, 215

Hybrid, fowls and grouse, 11;
fowl and peacock, 97;
pheasant and grouse, 97;
Azalea and Rhododendron, 97

Hybrids, gradation in sterility of, 11, 72, 97;
sterility of not reciprocal, 97;
variability of, 78;
compared and contrasted with mongrel, 107

Individual, meaning of term, 58

Inheritance of acquired characters, _see_ Character

Inheritance, delayed or latent, 43, 44 _n._, 223;
of character at a time of life corresponding to that at which it
first appeared, 43, 44 _n._, 223;
germinal, 44, 222, 223

Insect, adapted to fertilise flowers, 87;
feigning death, 123;
metamorphosis, 129;
variation in larvae, 223

Instinct, variation in, 17, 112;
and faculty, 18, 123;
guided by reason, 18, 19, 118;
migratory, 19;
migratory, loss of by woodcocks, 120;
migratory, origin of, 125;
due to germinal variation rather than habit, 116;
requiring education for perfection, 117;
characterised by ignorance of end: _e.g._ butterflies laying eggs,
17, 118;
butterflies laying eggs on proper plant, 118, 127;
instinct, natural selection applicable to, 19, 120

Instinct, for finding the way, 124;
periodic, _i.e._ for lapse of time, 124;
comb-making of bee, 125;
birds feeding you