« AnteriorContinuar »
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, 304.
Antarctic islands, ancient flora of,
of organic boings, 870. Antirrhinum, 146.
on groups of species suddenly glave-making instinct, 196.
neuter, structure of, 212.
Aphis, development of, 397.
on embryological characters, Arab horses, 33.
Aralo-Caspian Sea, 804.
of species, 291.
Asclepias, pollen of, 174.
Audubon on babits of frigato-bird,
on variation in birds'-nests,
on heron eating seeds, 848.
dogs of, 193.
extinct animals of, 304.
European plants in, 331.
Azara on flies destroying cattle, 87.
domestic, descended from Babington, Mr., on British plants,
Bamboo with hooks, 177.
Barrando, M., on Silurian colonies.
Barrande, M., on the succession | Boequet, M., on fossil Chthamalus,
Brent, Mr., on house-tumblors,
on hawks killing pigeons, 825.
Bronn on duration of specifio
hivo, not sucking the red 374.
Buckman on variation in plants, 10.
Cabbage, varieties of, crossed, 90.
with deficient tarsi, 122. Canary-birds, sterility of hybrids,
Cape de Verde Islands, 358.
Carrier-pigoons killed by hawks,
Cassini on flowers of compositæ,
footstops and remains of, in variation in habits of, 82.
curling tail when going to
of adeira, Bermuda, 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.
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 afinities, 387.
Alph., on low plants, widely
on widely ranging plants
on naturalisation, 104.
on winged seeds, 133.
on Alpine species sud.
on distribution of planta
with large seeds, 324.
on vegetation of Aug.
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, 826.
Dispersal, means of, 320.
Distribution, geographical, 305.
means of, 320.
Disuse, effects of, under nature,
Divergence of character, 101.
Division, physiological, of labour,
domestic instincts of, 192.
inherited civilisation of, 193