The Variation of Animals and Plants Under Domestication, 第 2 卷D. Appleton, 1887 |
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analogous animals and plants Antirrhinum appear become birds bred breeders breeds buds capsules cattle cause cells changed conditions chapter characters climate close interbreeding colour correlation crossed degree diseases distinct species dogs domestic races domesticated animals doubt effects extremely facts feathers female fertilised fertility flowers fowls Fritz Müller fruit Gard Gardener's Chronicle Gärtner gemmules given Hist horns horses hybrids individuals inherited insects instance Isidore Geoffroy Saint-Hilaire Journal kind Kölreuter large number larvæ liable maize male manner modified natural selection natural species nectarine niata observed occasionally offspring Oncidium flexuosum organs ovules pangenesis Paraguay parent parent-forms Parthenogenesis peculiar peloric period petals pigeons pigs pollen pollen-grains prepotent probably produced progenitor propagated racter remarks reproductive respect result reversion RICHARD ANTHONY PROCTOR seed seedlings seen sheep slight stamens sterility stripes structure tendency tion transmitted variability variations varieties various vary whilst wild yield Youatt Zoological Gardens
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第 426 頁 - If an architect were to rear a noble and commodious edifice without the use of cut stone, by selecting from the fragments at the base of a precipice wedge-form stones for his arches, elongated stones for his lintels, and flat stones for his roof, we should admire his skill and regard him as the paramount power. Now, the fragments of stone, though indispensable to the architect, bear to the edifice built by him the same relation which the fluctuating variations of organic beings bear to the varied...
第 428 頁 - ... no shadow of reason can be assigned for the belief that variations, alike in nature and the result of the same general laws, which have been the groundwork through natural selection of the formation of the most perfectly adapted animals in the world, man included, were intentionally and specially guided. However much we may wish it, we can hardly follow Professor Asa Gray in his belief that " variation has been led along certain beneficial lines," like a stream "along definite and useful lines...
第 250 頁 - Bachman 29 states that he has seen turkeys raised from the eggs of the wild species lose their metallic tints and become spotted with white in the third generation.
第 426 頁 - but the most distinct genera and orders within the same great class - for instance, mammals, birds, reptiles, and fishes - are all the descendants of one common progenitor, and we must admit that the whole vast amount of difference between these forms has primarily arisen from simple variability. To consider the subject under this point of view is enough to strike one dumb with amazement. But our amazement ought to be lessened when we reflect that beings almost infinite in number, during an almost...
第 370 頁 - Lastly, I assume that the gemmules in their dormant state have a mutual affinity for each other, leading to their aggregation into buds or into the sexual elements.