The Origin of Species by Means of Natural Selection: Or, The Preservation of Favored Races in the Struggle for Life, Volumen2AMS Press, 1972 |
Dentro del libro
Resultados 1-3 de 19
Página 40
... variability graduates away . When mongrels and the more fertile hybrids are propagated for several generations , an extreme amount of variability in the offspring in both cases is notorious ; but some few instances of both hybrids and ...
... variability graduates away . When mongrels and the more fertile hybrids are propagated for several generations , an extreme amount of variability in the offspring in both cases is notorious ; but some few instances of both hybrids and ...
Página 277
... variability when it has once come into play , does not cease under domestication for a very long period ; nor do we know that it ever ceases , for new varieties are still occasionally produced by our oldest domesticated productions ...
... variability when it has once come into play , does not cease under domestication for a very long period ; nor do we know that it ever ceases , for new varieties are still occasionally produced by our oldest domesticated productions ...
Página 338
... Variability of mongrels and hybrids , ii . 39 . Variation under domestication , i . 8 . caused by reproductive system being affected by conditions of life , i . 10 . under nature , i . 51 . laws of , i . 164 . correlated , i 13 , 177 ...
... Variability of mongrels and hybrids , ii . 39 . Variation under domestication , i . 8 . caused by reproductive system being affected by conditions of life , i . 10 . under nature , i . 51 . laws of , i . 164 . correlated , i 13 , 177 ...
Contenido
CONTENTS OF VOL | 1 |
CHAPTER X | 48 |
CHAPTER XII | 129 |
Derechos de autor | |
Otras 2 secciones no mostradas
Otras ediciones - Ver todas
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