The Origin of Species by Means of Natural Selection: Or, The Preservation of Favored Races in the Struggle for Life, Volumen2AMS Press, 1972 |
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Página 7
... pollen from a distinct species , but not by pollen from the same plant , though this pollen can be proved to be perfectly sound by fertilising other plants or species . In the genus Hippeastrum , in Corydalis as shown by Professor ...
... pollen from a distinct species , but not by pollen from the same plant , though this pollen can be proved to be perfectly sound by fertilising other plants or species . In the genus Hippeastrum , in Corydalis as shown by Professor ...
Página 12
... pollen produces . So in hybrids themselves , there are some which never have produced , and probably never would produce , even with the pollen of the pure parents , a single fertile seed : but in some of these cases a first trace of ...
... pollen produces . So in hybrids themselves , there are some which never have produced , and probably never would produce , even with the pollen of the pure parents , a single fertile seed : but in some of these cases a first trace of ...
Página 30
... pollen taken from stamens not corresponding in height with the pistil , differs much in degree , up to absolute and ... pollen of a distinct species be placed on the stigma of a flower , and its own pollen be afterwards , even after a ...
... pollen taken from stamens not corresponding in height with the pistil , differs much in degree , up to absolute and ... pollen of a distinct species be placed on the stigma of a flower , and its own pollen be afterwards , even after a ...
Contenido
CONTENTS OF VOL | 1 |
CHAPTER X | 48 |
CHAPTER XII | 129 |
Derechos de autor | |
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Términos y frases comunes
accumulated adapted admit adult affinity allied species ancient animals appear Archipelago arctic areas become beds believe birds breeds Cambrian changes characters classification climate closely allied continent crustaceans degree deposited difficulty distant distinct species domestic doubt embryo Europe existing extinct fact faunas fertilised fertility flowers formations formerly forms fossil fresh-water Fritz Müller Gärtner genera genus geological period geological record Glacial period groups of species habits hybrids hybrids produced important individuals inhabitants inherited insects instance intermediate intervals land larvæ less living mammals manner marine Marsupials migration modified descendants mongrels mountains natural selection naturalists nearly occur oceanic islands offspring organisation parent parent-form peculiar perfect pistil plants pollen present probably produced quadrupeds reciprocal crosses regions remains remarked reproductive resemblance rocks rudimentary organs seeds Silurian slight South America species belonging stage stamens sterility structure successive suppose terrestrial tertiary tion variations varieties whilst widely different wings