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 87
... plants , and these belonged to eighteen genera and to eight orders , which shows how much these plants differed from each other . So it is with the plants and insects on small and uniform islets : also in small ponds of fresh water ...
... plants , and these belonged to eighteen genera and to eight orders , which shows how much these plants differed from each other . So it is with the plants and insects on small and uniform islets : also in small ponds of fresh water ...
Página 203
... plants , but without making any use of this habit . Soon afterwards Fritz Müller discovered that the young stems of an Alisma and of a Linum , —plants which do not climb and are widely separated in the natural system , -revolved plainly ...
... plants , but without making any use of this habit . Soon afterwards Fritz Müller discovered that the young stems of an Alisma and of a Linum , —plants which do not climb and are widely separated in the natural system , -revolved plainly ...
Página 262
... plant . In the same manner as the sterility of hybrids does not always run parallel with the difficulty of making the first cross between the two parent - species , so the sterility of certain illegitimate plants was unusually great ...
... plant . In the same manner as the sterility of hybrids does not always run parallel with the difficulty of making the first cross between the two parent - species , so the sterility of certain illegitimate plants was unusually great ...
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