On the Origin of Species by Means of Natural Selection: Or The Preservation of Favored Races in the Struggle for Life, Volumen2D. Appleton, 1888 - 458 páginas |
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Página xvi
... America , ' published in 1836 , wrote ( p . 6 ) as follows : - " All species might have been varieties once , and many varieties are gradually becoming species by assuming constant and peculiar characters ; " but farther on ( p . 18 ) ...
... America , ' published in 1836 , wrote ( p . 6 ) as follows : - " All species might have been varieties once , and many varieties are gradually becoming species by assuming constant and peculiar characters ; " but farther on ( p . 18 ) ...
Página 1
... America , and in the geological relations of the present to the past inhabitants of that continent . These facts , as will be seen in the latter chapters of this volume , seemed to throw some light on the origin of species -- that ...
... America , and in the geological relations of the present to the past inhabitants of that continent . These facts , as will be seen in the latter chapters of this volume , seemed to throw some light on the origin of species -- that ...
Página 37
... America and Europe , which differ very slightly from each other , have been ranked by one eminent naturalist as undoubted species , and by another as varieties , or , as they are often called , geographical races ! Mr. Wallace , in ...
... America and Europe , which differ very slightly from each other , have been ranked by one eminent naturalist as undoubted species , and by another as varieties , or , as they are often called , geographical races ! Mr. Wallace , in ...
Página 38
... America and Europe is ample , will that between Europe and the Azores , or Madeira , or the Canaries , or between the several islets of these small archipelagos , be sufficient ? Mr. B. D. Walsh , a distinguished entomologist of the ...
... America and Europe is ample , will that between Europe and the Azores , or Madeira , or the Canaries , or between the several islets of these small archipelagos , be sufficient ? Mr. B. D. Walsh , a distinguished entomologist of the ...
Página 51
... America , and latterly in Australia , had not been well authenticated , they would have been incredible . So it is with plants ; cases could be given of introduced plants which have become common throughout whole islands n a period of ...
... America , and latterly in Australia , had not been well authenticated , they would have been incredible . So it is with plants ; cases could be given of introduced plants which have become common throughout whole islands n a period of ...
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Términos y frases comunes
adapted admit affinities allied species America analogous ancient appear Asa Gray beak become bees believe belonging birds breeds cause cells characters climate closely allied colour continued crossed crustaceans degree developed difficulty distinct species doubt effects eggs embryo existing extinct extremely facts favourable fertilised fertility flowers formation formerly forms fossil Fritz Müller genera genus geological geological period Glacial period gradations greater number habits Hence hybrids important 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 occur oceanic islands offspring organisation organs parent peculiar perfect pigeon pistil pollen present preserved principle probably produced quadrupeds ranked reciprocal crosses remarked reproductive resemblance rudimentary seeds sexual selection slight South America stamens sterility structure struggle successive supposed tend theory tion variability variations varieties vary whilst whole wings young