The Origin of Species by Means of Natural Selection, Or, The Preservation of Favored Races in the Struggle for Life, Volumes 1-2D. Appleton, 1917 - Evolution |
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Page 73
... range over 7.7 provinces ; whereas , the species to which these varieties belong range over 14.3 provinces . So that the acknowledged varieties have nearly the same restricted average range , as have the closely allied forms , marked ...
... range over 7.7 provinces ; whereas , the species to which these varieties belong range over 14.3 provinces . So that the acknowledged varieties have nearly the same restricted average range , as have the closely allied forms , marked ...
Page 211
... range of any one species , depending as it does on the range of others , will tend to be sharply defined . Moreover , each species on the confines of its range , where it exists in lessened numbers , will , dur- ing fluctuations in the ...
... range of any one species , depending as it does on the range of others , will tend to be sharply defined . Moreover , each species on the confines of its range , where it exists in lessened numbers , will , dur- ing fluctuations in the ...
Page 137
... range that their range is continuous . What a strange anomaly it would be , if a directly opposite rule were to prevail , when we go down one step lower in the series , namely , to the individuals of the same species , and these had not ...
... range that their range is continuous . What a strange anomaly it would be , if a directly opposite rule were to prevail , when we go down one step lower in the series , namely , to the individuals of the same species , and these had not ...
Contents
VARIATION UNDER DOMESTICATION | 7 |
CHAPTER II | 51 |
STRUGGLE FOR EXISTENCE | 66 |
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Common terms and phrases
adapted affinity allied species ancient animals appear Archipelago beak become believe belonging birds breeds Cambrian cause characters climate closely allied colour common continent crossed crustaceans degree developed difficulty distinct species domestic doubt eggs embryo Europe existing extinct extremely facts favourable fertilised fertility fish flowers formation formerly forms fossil Fritz Müller Gärtner genera genus geological geological period Glacial period gradations groups of species habits Hence hybrids hybrids produced important individuals inhabitants inherited insects instance instincts intercrossing intermediate land larvæ less living male mammals manner Marsupials migration modified descendants natural selection naturalists nearly occur oceanic islands offspring organisation parent peculiar perfect pigeon pistil plants pollen present probably produced progenitor quadrupeds ranked reciprocal crosses remarked resemblance seeds Silurian slight South America stage stamens sterility structure successive suppose theory tion variability variations varieties vary whilst whole widely different wings