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 |
Dentro del libro
Resultados 1-5 de 67
Página xii
... young cuckoos ejecting their foster - brothers confirmed . 268 270 307 240 215 319 248 326 252 377 284 402 301 440 328 463 343 505 373 516 On the cuckoo - like habits of the Molothrus . On fertile hybrid moths . The discussion on the ...
... young cuckoos ejecting their foster - brothers confirmed . 268 270 307 240 215 319 248 326 252 377 284 402 301 440 328 463 343 505 373 516 On the cuckoo - like habits of the Molothrus . On fertile hybrid moths . The discussion on the ...
Página 6
... young of the same litter , and in seedlings from the same seed - capsule . At long intervals of time , out of millions or individuals reared in the same country and fed on nearly the same food , deviations of structure so strongly ...
... young of the same litter , and in seedlings from the same seed - capsule . At long intervals of time , out of millions or individuals reared in the same country and fed on nearly the same food , deviations of structure so strongly ...
Página 7
... young ; whereas carnivorous birds , with the rarest exceptions , hardly ever lay fertile eggs . Many exotic plants have pollen utterly worthless , in the same condition as in the most sterile hybrids . When , on the one hand , we see ...
... young ; whereas carnivorous birds , with the rarest exceptions , hardly ever lay fertile eggs . Many exotic plants have pollen utterly worthless , in the same condition as in the most sterile hybrids . When , on the one hand , we see ...
Página 41
... young naturalist commences the study of a group of organisms quite unknown to him , he is at first much perplexed in determining what differences to consider as specific , and what as varietal ; for he knows nothing of the amount and ...
... young naturalist commences the study of a group of organisms quite unknown to him , he is at first much perplexed in determining what differences to consider as specific , and what as varietal ; for he knows nothing of the amount and ...
Página 51
... young in the interval , and surviving till one hundred years old ; if this be so , after a period of from 740 to 750 ... young , and that nearly all the young have been enabled to breed . Their geometrical ratio of increase , the result ...
... young in the interval , and surviving till one hundred years old ; if this be so , after a period of from 740 to 750 ... young , and that nearly all the young have been enabled to breed . Their geometrical ratio of increase , the result ...
Otras ediciones - Ver todas
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