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which is almost implied by reproduction ; Variability, from the indirect and direct action of the external conditions of life, and from use, and disuse ; a Ratio of Increase so high as to lead to a Struggle for Life, and as a consequence to Natural Selection, entailing Divergence of Character and the Extinction of less-improved forms. Thus, from the war of nature, from famine and death, the most exalted object which we are capable of conceiving, namely, the production of the higher animals, directly follows. There is grandeur in this view of life, with its several powers, having been originally breathed by the Creator into a few forms or into one ; and that, whilst this planet has gone cycling on according to the fixed law of gravity, from so simple a beginning endless forms most beautiful and most wonderful have been, and are being, evolved.
ABERRANT groups, 886.
Animals, oxtinct, of Australia, 804.
Antarctic islands, ancient flora of,
son groups of species suddenly - slave-making instinct, 196.
- nouter, structure of, 212.
Aphis, development of, 397.
Aralo-Caspian Sea, 804.
of species, 291.
Asclepias, pollen of, 174.
Asses, striped, 147.
Audubon on babits of frigato-bird,
- on variation in birds'-neste,
on heron eating seeds, 848.
- dogs of, 193.
European plants in, 831.
Azara on flies destroying cattlo, 67.
being variable, 16.
Bamboo with hooks, 177.
Barrando, M., on Silurian colonias.
Barrande, M., on the succession | Bosquet, M., on fossil Chthamalus,
On affinities of ancient species, Branchiæ, 171.
Brent, Mr., on house-tumblers,
Bronn on duration of specifio
hivo, not sucking the rod 874.
Buckman on variation in plants, 10.
Cabbage, varieties of, crossed, 90.
with deficient tarsi, 122. Canary-birds, sterility of hybrids,
Capo de Verde Islands, 358.
Carrier-pigoons killed by hawks,
Cassini on flowers of composite,
footsteps and remains of, in 'variation in habits of, 82.
- curling tail when going to
of Madeira, Bormuda, and Cattle destroying fir-trees, 66.
- destroyed by flies in La Plata,
breeds of, locally extinct, 100.
--- fertility of Indian and Euro-
pean breeds, 228.
Centres of creation, 316.
Cepbalopodæ, development of, 397.
Characters, divergence of, 101.
sexual, variable, 152.
adaptive or analogical, 884.
- mutual, 67.
Otonomys, blind, 124.
Currants, grafts of, 235.
to natural selection, 92 185.
- Fred., on instinct, 187.
Dana, Prof., on blind cave-animals,
on relations of crustaceans of
on crustaceans of New Zea.
De Candolle on struggle for exist-
- on umbellifera, 132.
-on general affinities, 387.
-- Alph., on low plants, widely
- on widely ranging plants
- on naturalisation, 104.
- On Alpine species sud.
on distribution of planta
with large seeds, 324.
on vegetation of Aus.
-- on fresh-water plants,
on insular plants, 349.
favourable to fertility, 239. Denudation, rate of, 256.
of oldest rocks, 276.
Devonian system, 299.
Dirt on feet of birds, 326.
Dispersal, means of, 820.
Distribution, geographical, 305.
- means of, 320.
Disuse, effects of, under nature,
Divergence of character, 101.
Division, physiological, 'of labour,
portanco in altering breeds, 18. Dogs, hairless, with imperfect
domestic instincts of, 192.
inherited civilisation of, 193.