Mueller, 293.

Mutation theory, 146.

Naegeli, 143, 148.

Natural Selection,
doctrine of, 116, 117, 118;
the struggle for existence, 124, 125;
simply trial and error, 131;
Darwin recognized it as incomplete, 142;
germ-plasm theory supplements, 145.

Nebula, gaseous, 84.

Nervous systems, 201, 202, 205, 206, 211;
of worker-bee, 232.

Niagara, 85, 86, 89.

Ontogeny, recapitulates phylogeny, 63.

Orang-outang, 163, 164.

Orders, 32.

Organic, 15;
systems, 17;
transformation, analogies of, 43,
a real and natural process, 55, 56, 76;
mechanism, alteration of, 55.

Organisms,
living, 14;
analysis of, 16; 17, 18, 19, 26, 28, 29, 31, 32;
characteristic early stages, 55;
are they adapted by circumstances? 109;
environment, 111;
physical heritage of, 113;
variation of, 119;
difference, 121;
universal conflict of, 127;
change, 130;
human, 32, 156, 159, 165-171;
nervous system of, 201;
psychical characteristics of, 202;
many-celled, 257.

Organs, 16, 17, 28;
of human body, 156.

Origin of Species, 136, 149.

Origination of new parts, 109.

Osborn, 148.

Ostrich, 44.

Over production, 122-124, 129.

Owls, horned, of Arizona, 45; 139.

Palaeontology, 32, 34, 73, 74, 76;
evidence of, not complete, 80, 81;
table of facts of, 91; 94;
second division of evidence, 95;
does it throw light on antiquity of man? 155;
of mind, 202, 203, 217.

Paludina, 95.

Partulae, 103.

Pearson, Karl, 6, 7, 142, 147;
heredity of mental qualities, 232.

Penguin, a counterpart of the seal, 44.

Peoples,
fusion of, 178, 179;
Mexicans, 178, 181;
Anglo-Saxon, 179;
American, 179;
Indians, 181, 183, 185, 191, 192;
Patagonian, 180, 192;
Polynesian, 181, 182, 187;
Moor, 181;
Zulu, 181, 183;
Malay, 181, 183, 190;
Mongolian, 181, 186-190;
Papuan, 182;
Negro, African, Ethiopian, 182, 183, 192-195;
Caucasian, 182, 185-189, 195;
Veddahs, 182, 188;
European, 183;
Asiatic, 183;
Laplander, 183, 190;
Scandinavian types,
Norwegians, Swedes, Danes, Germans--north and south--186, 187;
types of, 186-196;
Persians, 186,
eastern, 187;
Afghans, Hindus, 186;
Welsh, French, Swiss, 187;
Russians, 187-190;
Poles, Armenians, 187;
Mediterranean type,
Spaniard, Italian, Greek, Arab, 187;
subordinate group,
Semitic, Arab, Hebrew, 187;
North African, Berber, Hamites, 187;
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