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Página 47 - I can see no difficulty in a race of bears being rendered, by natural selection, more and more aquatic in their structure and habits, with larger and larger mouths, till a creature was produced as monstrous as a whale.
Página 53 - There is grandeur in this view of life, with its several powers, having been originally breathed by the Creator into a few forms or into one; and that, whilst this planet has gone cycling on according to the fixed law of gravity, from so simple a beginning endless forms most beautiful and most wonderful have been, and are being evolved.
Página 47 - ... of the year when food was scarcest; they would also rear more young, which would tend to inherit these slight peculiarities. The less fleet ones would be rigidly destroyed. I can see no more reason to doubt that these causes in a thousand generations would produce a marked effect, and adapt the form of the fox or dog to the catching of hares instead of rabbits, than that greyhounds can be improved by selection and careful breeding.
Página 53 - sees grandeur in the " view of life, with its several powers, having been originally breathed by the Creator into a few forms or into one : " ' ' Derivation ' sees, therein, a narrow invocation of a special miracle and an unworthy limitation of creative power, the grandeur of which is manifested daily. hourly, in calling into life many forms, by conversion of physical...
Página 51 - Not one hour old, yet of sciential brain To unperplex bliss from its neighbour pain ; Define their pettish limits, and estrange Their points of contact, and swift counterchange ; Intrigue with the specious chaos, and dispart Its most ambiguous atoms with sure art ; As though in Cupid's college she had spent Sweet days a lovely graduate, still unshent, And kept his rosy terms in idle languishment.
Página 444 - P.). Report on the Filtration of River Waters for the supply of Cities, as practised in Europe, made to the Board of Water Commissioners of the City of St. Louis.
Página 52 - Derivation holds that every species changes in time, by virtue of inherent tendencies thereto. ' Natural Selection ' holds that no such change can take place without the influence of altered external circumstances.
Página 98 - ... number of known species which form the groundwork of zoological science is always increasing, and our knowledge of their structure becomes more complete, fresh generalizations continually occur to the naturalist, and the number of genera and other groups requiring appellations is ever becoming more extensive. It thus becomes necessary to subdivide the contents of old groups and to make their definitions continually more restricted. In carrying out this process, it is an act of justice to the...
Página 96 - For these reasons, we have no hesitation in adopting as our fundamental maxim, the " law of priority," viz. § 1. The name originally given by the founder of a group or the describer of a species should be permanently retained, to the exclusion of all subsequent synonyms (with the exceptions about to be noticed) . Having laid down this principle, we must next inquire into the limitations which are found necessary in carrying it into practice.