The American Journal of Science and ArtsS. Converse, 1860 |
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Стр. 3
... fact , that the number of known species of flowering plants is by some assumed to be under 80,000 , and by others over 150,000 . estimated by one mind and eye , the errors made J. D. Hooker , Introductory Essay to the Flora of Tasmania . 3.
... fact , that the number of known species of flowering plants is by some assumed to be under 80,000 , and by others over 150,000 . estimated by one mind and eye , the errors made J. D. Hooker , Introductory Essay to the Flora of Tasmania . 3.
Стр. 5
... facts derived from a study of classification ; secondly , from distribution ; thirdly , from fossils ; after which I shall ex- amine the theories with which these facts should harmonize . §2 . On the General Phenomena of Variation in ...
... facts derived from a study of classification ; secondly , from distribution ; thirdly , from fossils ; after which I shall ex- amine the theories with which these facts should harmonize . §2 . On the General Phenomena of Variation in ...
Стр. 7
... fact is , that this element of mutability pervades the whole vegetable kingdom ; no class nor order nor genus of more than a few species claims absolute exemption , whilst the grand total of unstable forms generally assumed to be ...
... fact is , that this element of mutability pervades the whole vegetable kingdom ; no class nor order nor genus of more than a few species claims absolute exemption , whilst the grand total of unstable forms generally assumed to be ...
Стр. 8
... fact of the best limited groups being most prevalent among the higher classes ( i . e . , among those most complicated in their organization ) , would at first sight appear an argument against progression , were it not for the ...
... fact of the best limited groups being most prevalent among the higher classes ( i . e . , among those most complicated in their organization ) , would at first sight appear an argument against progression , were it not for the ...
Стр. 11
... fact of almost every member of our Flora Cibaria . This would not be so were their any disposition in the neglected cultivated races to revert to the wild form . little tendency to reversion . * With this law the J. D. Hooker ...
... fact of almost every member of our Flora Cibaria . This would not be so were their any disposition in the neglected cultivated races to revert to the wild form . little tendency to reversion . * With this law the J. D. Hooker ...
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acid American ammonia animals antimony appears arsenic atomic weight aurora Australia beds bismuth carbon carbonic acid Carboniferous character chemical chlorid coast color containing Cretaceous crystals Dép described determine Dicotyledons direction dolomite equivalent existing fact flame flora fluorine formation formula fossil genera genus geographical geological gives gypsum horizon inches iridium iron Journal jurassic known lake less light lignite limestone magnetic mass matter metals meteor miles mineral mountains natural nearly northern observations obtained occur organic orthoclase osmium oxyd oxygen paper pectolite peculiar Permian phenomena phosphorus pieces plants plates platinum portion potash present Prof radials ratio relations remarkable river rocks ruthenium salt scientific SECOND SERIES Sept silica soda solution southern species specimens strata substance supposed surface temperature Tertiary theory tion upper variation varieties vegetation volume whole XXIX
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Стр. 148 - As all the living forms of life are the lineal descendants of those which lived long before the Cambrian epoch, we may feel certain that the ordinary succession by generation has never once been broken, and that no cataclysm has desolated the whole world. Hence we may look with some confidence to a secure future of great length. And as natural selection works solely by and for the good of each being, all corporeal and mental endowments will tend to progress towards perfection.
Стр. 147 - Judging from the past, we may safely infer that not one living species will transmit its unaltered likeness to a distant futurity. And of the species now living very few will transmit progeny of any kind to a far distant futurity...
Стр. 148 - I believe that animals have descended from at most only four or five progenitors, and plants from an equal or lesser number.
Стр. 158 - The limbs divided into great branches, and these into lesser and lesser branches, were themselves once, when the tree was small, budding twigs; and this connexion of the former and present buds by ramifying branches may well represent the classification of all extinct and living species in groups subordinate to groups.
Стр. 172 - When we travel southward and see a species decreasing in numbers, we may feel sure that the cause lies quite as much in other species being favored as in this one being hurt.
Стр. 170 - We behold the face of nature bright with gladness, we often see superabundance of food; we do not see, or we forget, that the birds which are idly singing round us mostly live on insects or seeds, and are thus constantly destroying life ; or we forget how largely these songsters, or their eggs, or their nestlings, are destroyed by birds and beasts of prey...
Стр. 170 - Nothing is easier than to admit in words the truth of the universal struggle for life, or more difficult — at least I have found it so — than constantly to bear this conclusion in mind.
Стр. 159 - ... extinct and living species in groups subordinate to groups. Of the many twigs which flourished when the tree was a mere bush, only two or three, now grown into great branches, yet survive and bear the other branches ; so with the species which lived during long-past geological periods, very few have left living and modified descendants.
Стр. 449 - THE BOYDEN PREMIUM URIAH A. BOYDEN, ESQ., of Boston, Mass., has deposited with THE FRANKLIN INSTITUTE the sum of one thousand dollars, to be awarded as a premium to "Any resident of North America who shall determine by experiment whether all rays of light,* and other physical rays, are or are not transmitted with the same velocity.
Стр. 158 - At each period of growth all the growing twigs have tried to branch out on all sides, and to overtop and kill the surrounding twigs and branches, in the same manner as species and groups of species have at all times overmastered other species in the great battle for life.