On the Origin of Species by Means of Natural Selection, Or, The Preservation of Favoured Races in the Struggle for LifeAppleton, 1898 |
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Página 119
... naturalists maintain that molluscs were formerly more highly developed than at present ; but a stronger case can be made out on the opposite side , by consider- ing the vast reduction of brachiopods , and the fact that our existing ...
... naturalists maintain that molluscs were formerly more highly developed than at present ; but a stronger case can be made out on the opposite side , by consider- ing the vast reduction of brachiopods , and the fact that our existing ...
Página 131
... naturalists to believe that the isthmus was formerly open . West- ward of the shores of America , a wide space of open ocean extends , with not an island as a halting - place for emigrants ; here we have a barrier of another kind , and ...
... naturalists to believe that the isthmus was formerly open . West- ward of the shores of America , a wide space of open ocean extends , with not an island as a halting - place for emigrants ; here we have a barrier of another kind , and ...
Página 135
... naturalists , namely , whether species have been created at one or more points of the earth's sur- face . Undoubtedly there are many cases of extreme difficulty in understanding how the same species could possibly have CHAP . XII ...
... naturalists , namely , whether species have been created at one or more points of the earth's sur- face . Undoubtedly there are many cases of extreme difficulty in understanding how the same species could possibly have CHAP . XII ...
Página 137
... naturalists that the most natural genera , or those genera in which the species are most closely related to each other , are generally confined to the same country , or if they have a wide range that their range is continuous . What a ...
... naturalists that the most natural genera , or those genera in which the species are most closely related to each other , are generally confined to the same country , or if they have a wide range that their range is continuous . What a ...
Página 157
... naturalists rank as geo- graphical races , and others as distinct species ; and a host of closely allied or representative forms which are ranked by all naturalists as specifically distinct . As on the land , so in the waters of CHAP ...
... naturalists rank as geo- graphical races , and others as distinct species ; and a host of closely allied or representative forms which are ranked by all naturalists as specifically distinct . As on the land , so in the waters of CHAP ...
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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