On the Origin of Species by Means of Natural Selection: Or, The Preservation of Favoured Races in the Struggle for LifeEaston Press, 1976 - 470 páginas |
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Página 178
... considered by De Candolle to be in other species of the highest systematic importance . Prof. Braun mentions a Fumariaceous genus , in which the flowers in the lower part of the spike bear oval , ribbed , one - seeded nutlets ; and in ...
... considered by De Candolle to be in other species of the highest systematic importance . Prof. Braun mentions a Fumariaceous genus , in which the flowers in the lower part of the spike bear oval , ribbed , one - seeded nutlets ; and in ...
Página 206
... considered , and the others will hereafter be considered . They seem to me to partake little of the character of demonstration , and to have little weight in comparison with those in favour of the power of natural selection , aided by ...
... considered , and the others will hereafter be considered . They seem to me to partake little of the character of demonstration , and to have little weight in comparison with those in favour of the power of natural selection , aided by ...
Página 386
... considered as the same individual . He includes monsters and varieties , not from their partial resemblance to the parent - form , but because they are descended from it . As descent has universally been used in classing together the ...
... considered as the same individual . He includes monsters and varieties , not from their partial resemblance to the parent - form , but because they are descended from it . As descent has universally been used in classing together the ...
Contenido
VARIATION UNDER NATURE | 30 |
STRUGGLE FOR EXISTENCE | 45 |
NATURAL SELECTION | 59 |
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Términos y frases comunes
accumulated adapted admit affinities allied species America ancient appear beak become bees believe belonging birds breeds cause cells characters climate closely allied colour common progenitor continuous crossed crustaceans degree developed difficulty distinct species divergence doubt effects eggs embryo existing exterminated extinct extremely facts favourable fertilised fertility flowers formation forms fossil Fritz Müller genera genus geological geological period gradations greater number groups of species habits Hence hybrids hybrids produced important increase individuals inhabitants inherited insects instance instincts intercrossing intermediate kind lamellæ larvæ less living male mammals manner marsupials migration modified descendants natural selection naturalists nearly nest occasionally offspring organisation organs Origin of Species parent peculiar perfect pigeons pistil plants pollen present preserved principle probably produced quadrupeds ranked reciprocal crosses remarked resemblance rudimentary seeds slight South America stamens sterility structure struggle successive supposed swimbladder theory variability variations varieties vary whilst whole wings young