The Origin of Species by Means of Natural Selection: Or, the Preservation of Favored Races in the Struggle for Life, Volumen1D. Appleton, 1898 |
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Página viii
... bees - Slave - making ants - Hive - bee , its cell - making instinct - Changes of instinct and structure not necessarily simultaneous - Difficulties of the theory of the Natural Selection of instincts - Neuter or sterile insects Summary ...
... bees - Slave - making ants - Hive - bee , its cell - making instinct - Changes of instinct and structure not necessarily simultaneous - Difficulties of the theory of the Natural Selection of instincts - Neuter or sterile insects Summary ...
Página 90
... bees do not visit this flower . I have also found that the visits of bees are necessary for the fertilisation of some kinds of clover ; for instance , 20 heads of Dutch clover ( Trifolium repens ) yielded 2,290 seeds , but 20 other ...
... bees do not visit this flower . I have also found that the visits of bees are necessary for the fertilisation of some kinds of clover ; for instance , 20 heads of Dutch clover ( Trifolium repens ) yielded 2,290 seeds , but 20 other ...
Página 91
... bees more numerous than elsewhere , which I attribute to the number of cats that destroy the mice . " Hence it is quite credible that the presence of a feline animal in large numbers in a district might deter- mine , through the ...
... bees more numerous than elsewhere , which I attribute to the number of cats that destroy the mice . " Hence it is quite credible that the presence of a feline animal in large numbers in a district might deter- mine , through the ...
Página 93
... bee is rapidly exterminating the small , stingless native bee . One spe- cies of charlock has been known to supplant another species. CHAP . III . ] 93 STRUGGLE FOR EXISTENCE .
... bee is rapidly exterminating the small , stingless native bee . One spe- cies of charlock has been known to supplant another species. CHAP . III . ] 93 STRUGGLE FOR EXISTENCE .
Página 115
... bees , never- theless every female flower which I examined had been effectually fertilised by the bees , which had flown from tree to tree in search of nectar . But to return to our imaginary case : as soon as the plant had been ...
... bees , never- theless every female flower which I examined had been effectually fertilised by the bees , which had flown from tree to tree in search of nectar . But to return to our imaginary case : as soon as the plant had been ...
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Términos y frases comunes
adapted advantage allied analogous animals and plants appear Asa Gray beak become bees believe birds breeds caudicle cause cells characters climate closely colour common crossed cuckoo degree descendants developed difficulty distinct species disuse divergence domestic animals domestic races doubt effects eggs existence extinct extremely facts favourable females flowers forms Fritz Müller genera genus giraffe gradations greater number groups habits Hence hermaphrodites hive-bee important increase inhabitants inherited insects instance instincts intercrossing intermediate kind lamellæ large number larger genera larvæ less males manner Melipona Mivart modified natural selection naturalists nearly nest occasionally offspring organisation organs origin Origin of Species parent perfect period pigeons pollen pollen-grains present preserved prey principle probably produced progenitor quadrupeds rank rarely Red Grouse relation remarked resemble rock-pigeon seeds sexes sexual selection slight stamens striped structure struggle supposed swimbladder tend tendency tion tree variability variations varieties vary widely wings young