The Origin of Species by Means of Natural Selection: Or the Preservation of Favored Races in the Struggle for LifeD. Appleton, 1904 - 435 páginas |
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Página 34
... land or mountain pasture , with the wool of one breed good for one purpose , and that of another breed for another purpose ; when we compare the many breeds of dogs , each good for man in different ways ; when we compare the game - cock ...
... land or mountain pasture , with the wool of one breed good for one purpose , and that of another breed for another purpose ; when we compare the many breeds of dogs , each good for man in different ways ; when we compare the game - cock ...
Página 47
... land plays a part . Wandering savages or the inhabitants of open plains rarely possess more than one breed of the same species . Pigeons can be mated for life , and this is a great convenience to the fancier , for thus many races may be ...
... land plays a part . Wandering savages or the inhabitants of open plains rarely possess more than one breed of the same species . Pigeons can be mated for life , and this is a great convenience to the fancier , for thus many races may be ...
Página 65
... land - shells in Madeira , and with plants by Gaston de Saporta . If a variety were to flourish so as to exceed in numbers the parent species , it would then rank as the species , and the species as the variety ; or it might come to ...
... land - shells in Madeira , and with plants by Gaston de Saporta . If a variety were to flourish so as to exceed in numbers the parent species , it would then rank as the species , and the species as the variety ; or it might come to ...
Página 88
... land having been enclosed , so that cattle could not enter . But how im- portant an element enclosure is , I plainly saw near Farnham , in Surrey . Here there are extensive heaths , with a few clumps of old Scotch firs on the distant ...
... land having been enclosed , so that cattle could not enter . But how im- portant an element enclosure is , I plainly saw near Farnham , in Surrey . Here there are extensive heaths , with a few clumps of old Scotch firs on the distant ...
Página 94
... land being already thickly clothed with other plants ; so that the seeds may be widely dis- tributed and fall on unoccupied ground . In the water- beetle , the structure of its legs , so well adapted for div- ing , allows it to compete ...
... land being already thickly clothed with other plants ; so that the seeds may be widely dis- tributed and fall on unoccupied ground . In the water- beetle , the structure of its legs , so well adapted for div- ing , allows it to compete ...
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Términos y frases comunes
adapted affinities allied species America ancient appear Asa Gray beak become bees believe belonging birds breeds cause cells characters climate closely allied colour common continent crossed crustaceans degree developed difficulty distinct species domestic doubt effects eggs embryo existing extinct extremely facts favourable fertilised fertility flowers formation forms fossil Fritz Müller genera genus geological geological period Glacial period gradations greater number groups of species habits Hence hybrids important individuals inhabitants inherited insects instance instincts intercrossing intermediate kind lamellæ larvæ less living males mammals manner marsupials migration modified descendants natural selection naturalists nearly nest occasionally offspring organisation organs parent peculiar perfect pigeon pistil pollen present principle probably produced progenitor quadrupeds ranked remarked resemblance rudimentary seeds sexual selection Silurian slight South America stamens sterility structure successive supposed swimbladder tend theory tion trees variability variations varieties vary whilst whole wings young