The Origin of Species by Means of Natural Selection,: Or the Preservation of Favoured Races in the Struggle for LifeAppleton, 1898 - 432 páginas |
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Página 8
... habit , re- produces itself as perfectly as if it had been a natural species from the mountains of Chili . " I have taken some pains to ascertain the degree of fertility of some of the complex crosses of Rhododendrons , and I am assured ...
... habit , re- produces itself as perfectly as if it had been a natural species from the mountains of Chili . " I have taken some pains to ascertain the degree of fertility of some of the complex crosses of Rhododendrons , and I am assured ...
Página 10
... important osteological differences , as well as from those by Mr. Blyth on their differences in habits , voice , constitution , & c . , these two forms must be regarded as good and distinct species . 10 [ CHAP . IX . HYBRIDISM .
... important osteological differences , as well as from those by Mr. Blyth on their differences in habits , voice , constitution , & c . , these two forms must be regarded as good and distinct species . 10 [ CHAP . IX . HYBRIDISM .
Página 14
... habit and general appearance , and having strongly marked differ- ences in every part of the flower , even in the pollen , in the fruit , and in the cotyledons , can be crossed . An- nual and perennial plants , deciduous and evergreen ...
... habit and general appearance , and having strongly marked differ- ences in every part of the flower , even in the pollen , in the fruit , and in the cotyledons , can be crossed . An- nual and perennial plants , deciduous and evergreen ...
Página 27
... habits of life . Again , both with plants and animals , there is the clearest evidence that a cross between individuals of the same species , which differ to a certain extent , gives vigour and fer- tility to the offspring ; and that ...
... habits of life . Again , both with plants and animals , there is the clearest evidence that a cross between individuals of the same species , which differ to a certain extent , gives vigour and fer- tility to the offspring ; and that ...
Página 59
... habits deep water , and this has been found fossil in Sicily , whereas not one other species has hitherto been found in any tertiary formation : yet it is known that the genus Chthamalus existed during the Chalk period . Lastly , many ...
... habits deep water , and this has been found fossil in Sicily , whereas not one other species has hitherto been found in any tertiary formation : yet it is known that the genus Chthamalus existed during the Chalk period . Lastly , many ...
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Términos y frases comunes
admit affinity allied species ancient animals appear Archipelago arctic areas become believe birds Cambrian changes characters cies classification climate closely allied common progenitor continent crustaceans degree deposited difficulty distant distinct species domestic doubt embryo eral 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 sediment seeds Silurian South America stage stamens sterility structure successive suppose terrestrial tertiary theory tion variations varieties whilst widely different wings