The Principles of Biology, Volumen1Williams and Norgate, 1864 |
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Términos y frases comunes
acid Acrogens actions adaptation aggregate alterations Amphibia arise arrangement assimilation atoms become binary compounds birds body carbonic carbonic acid cause cells changes chemical colloids combination complex compounds connexion constituting continuous contrasts correspondence creatures crustaceans crystalloids Darwin definite degree differentiation direct equilibration displayed distinct divergence effects embryo environment ethereal waves evidence exhibit exist external facts Faunas fertilized germ functions further gamogenesis genesis greater groups growth habitats habitually heat Hence heterogeneity higher Hydrozoa hypothesis of evolution implies incident forces increase individuals inorganic kind less living mammals manifest mass ment modes modifications molecular mobility Mollusca motion moving equilibrium multiplication muscles natural selection nitrogenous nutriment nutrition offspring organic matter oviparous ovum oxygen parent parthenogenesis peculiarity phenomena physiological units polype produced Protozoa races re-actions re-distribution relations result similarly special creations species stamens structure substances successive temperature tion tissues truth types undergo unlike variations vertebral Vertebrata vital
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Página 265 - is a definite combination of heterogeneous changes, both simultaneous and successive, in correspondence with external coexistences and sequences.
Página 244 - That most skilful breeder, Sir John Sebright, used to say, with respect to pigeons, that "he would produce any given feather in three years, but it would take him six years to obtain head and beak.
Página 18 - Although chemically inert in the ordinary sense, colloids possess a compensating activity of their own, arising out of their physical properties. While the rigidity of the crystalline structure shuts out external impressions, the softness of the gelatinous colloid partakes of fluidity, and enables the colloid to become a medium for liquid diffusion, like water itself.
Página 177 - It is a corollary from that primordial truth which, as we have seen, underlies all other truths, that whatever amount of power an organism expends in any shape is the correlate and equivalent of a power that was taken into it from without.
Página 406 - ... existence of those animal species that actually exemplify it. To what natural laws or secondary causes the orderly succession and progression of such organic phenomena may have been committed, we, as yet, are ignorant.
Página 20 - The inquiry suggests itself whether the colloid molecule may not be constituted by the grouping together of a number of smaller crystalloid molecules, and whether the basis of colloidality may not really be this composite character of the molecule.
Página 63 - Life is a series of definite and successive changes, both of structure and composition, which take place within an individual without destroying its identity.
Página 67 - ... state. An inorganic body cannot be oxidized, without being at the same time changed in weight, colour, atomic arrangement, temperature, and electric condition. And in some...
Página 249 - Kentucky, are blind. In some of the crabs the foot-stalk for the eye remains, though the eye is gone ; — the stand for the telescope is there, though the telescope with its glasses has been lost. As it is difficult to imagine that eyes, though useless, could be in any way injurious to animals living in darkness, their loss may be attributed to disuse.
Página 402 - This wonderful relationship in the same continent between the dead and the living, will, I do not doubt, hereafter throw more light on the appearance of organic beings on our earth and their disappearance from it than any other class of facts.