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 |
Dentro del libro
Resultados 1-3 de 72
Página 37
... never varying on the same tree , and never found connected by intermediate states . After this discussion , the result of so much labour , he emphatically remarks : “ They are mistaken , who repeat that the greater part of our species ...
... never varying on the same tree , and never found connected by intermediate states . After this discussion , the result of so much labour , he emphatically remarks : “ They are mistaken , who repeat that the greater part of our species ...
Página 49
... never destroyed , and could be ensured to germinate in a fitting place . So that , in all cases , the average number of any animal or plant depends only indirectly on the number of its eggs or seeds . In looking at Nature , it is most ...
... never destroyed , and could be ensured to germinate in a fitting place . So that , in all cases , the average number of any animal or plant depends only indirectly on the number of its eggs or seeds . In looking at Nature , it is most ...
Página 165
... never has a gaily - coloured corolla . Several plants habitually produce two kinds of flowers ; one kind open and coloured so as to attract insects ; the other closed , not coloured , destitute of nectar , and never visited by insects ...
... never has a gaily - coloured corolla . Several plants habitually produce two kinds of flowers ; one kind open and coloured so as to attract insects ; the other closed , not coloured , destitute of nectar , and never visited by insects ...
Contenido
VARIATION UNDER NATURE | 30 |
STRUGGLE FOR EXISTENCE | 45 |
NATURAL SELECTION | 59 |
Derechos de autor | |
Otras 13 secciones no mostradas
Otras ediciones - Ver todas
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