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The Variation of Animals and Plants Under Domestication, V2
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according action animals appear authority become believe birds body bred breed buds cattle cause certain chapter characters Chronicle climate close colour common constitution crossed cultivated derived distinct dogs domesticated doubt effects exist extremely facts female fertilised fertility flowers fowls fruit Gardens gemmules give given greater growth hand head horses hybrids important improved increased individuals inherited instance Journal kind known less male manner modified namely natural nearly never observed occasionally occur offspring organs parent period pigeons pigs plants pollen possible present principle probably produced races raised rarely remarks reproductive respect result reversion says seed seen selection sexual sheep shown slight sometimes species sterility structure successive tion transmitted valued variability variations varieties various vary whilst whole wild yield young
Pagina 488 - XVIII. The Nature of Light. With a General Account of Physical Optics. By Dr. Eugene Lommel. With 188 Illustrations and a Table of Spectra in Chromo-lithography.
Pagina 481 - ... from giving a fuller account of these suggestive essays, only because we are sure that our readers will find it worth their while to peruse the book for themselves ; and we sincerely hope that the forthcoming parts of the 'International Scientific Series
Pagina 487 - ... science — the Chemistry of Light — and, in giving a popular view to the one, Dr. Vogel has presented an analysis of the principles and processes of the other. His treatise is as entertaining as it is instructive, pleasantly combining a history of the progress and practice of photography — from the first rough experiments of Wedgwood and Davy with sensitized paper, in 1802, down to the latest improvements of the art — with technical illustrations of the scientific theories on which the...
Pagina 412 - ... 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 ground-work 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...
Pagina 484 - ... but can be reduced to similar formula. The work is profusely illustrated, and, without reference to the theory it is designed to expound, will be regarded as a valuable addition to natural history.
Pagina 23 - As a general rule, crossed offspring in the first generation are nearly intermediate between their parents, but the grandchildren and succeeding generations continually revert, in a greater or lesser degree, to one or both of their progenitors.
Pagina 75 - Unless the characteristics and conformation of the two breeds are altogether averse to each other, nature opposes no barrier to their successful admixture ; so that, in the course of time, by the aid of selection and careful weeding, it is practicable to establish a new breed altogether.
Pagina 481 - The ' Forms of Water,' by Professor Tyndall, is an interesting and instructive little volume, admirably printed and illustrated. Prepared expressly for this series, it is in some measure a guarantee of the excellence of the volumes that will follow, and an indication that the publishers will spare no pains to include in the series the freshest investigations of the best scientific minds."—Boston Journal.
Pagina 483 - For, to those advanced students who have kept well abreast of the chemical tide, it offers a calm philosophy. To those others, youngest of the class, who have emerged from the schools since new methods have prevailed, it presents a generalization, drawing to its use all the data, the relations of which...