The Doctrine of Descent and DarwinismD. Appleton, 1875 - 334 من الصفحات |
من داخل الكتاب
النتائج 1-5 من 17
الصفحة 46
... transition taking place throughout organic Nature . In the cases of alternate generation selected above , the generations which do not produce ova and spermatozoa , reproduce themselves by external gemma- tion . Now , there is ...
... transition taking place throughout organic Nature . In the cases of alternate generation selected above , the generations which do not produce ova and spermatozoa , reproduce themselves by external gemma- tion . Now , there is ...
الصفحة 67
... and 6000 metres , the Devonian and Silurian formations , are the lowest , and therefore the first which clearly bear the mark of their origin as marine deposits . Both groups were formerly comprised under the name of Transition rocks.
... and 6000 metres , the Devonian and Silurian formations , are the lowest , and therefore the first which clearly bear the mark of their origin as marine deposits . Both groups were formerly comprised under the name of Transition rocks.
الصفحة 68
... Transition rocks , or Graywacke formation . In them also sandy , clayey , and chalky rocks alternate with one another , already exhibiting modifications of a local nature , from which , towards the carboniferous period , issued the ...
... Transition rocks , or Graywacke formation . In them also sandy , clayey , and chalky rocks alternate with one another , already exhibiting modifications of a local nature , from which , towards the carboniferous period , issued the ...
الصفحة 71
... Transition rocks , the surface of the earth had assumed , at least in places , a more smiling appearance . Here begins the first record of terrestrial plants . As to the character of the fauna , the rapid decrease of the Trilobites is ...
... Transition rocks , the surface of the earth had assumed , at least in places , a more smiling appearance . Here begins the first record of terrestrial plants . As to the character of the fauna , the rapid decrease of the Trilobites is ...
الصفحة 96
... transition of the forms succeeding one another historically in the strata of the earth . A highly instructive ... transitions to the succeeding forms . The intermediate layers furnish evidence that the other forms originated by ...
... transition of the forms succeeding one another historically in the strata of the earth . A highly instructive ... transitions to the succeeding forms . The intermediate layers furnish evidence that the other forms originated by ...
طبعات أخرى - عرض جميع المقتطفات
عبارات ومصطلحات مألوفة
according adaptation already Ammonites Amphibians animal world apes appearance Ascidian become birds brain causes Cetacea character characteristics comparative anatomy complete connection continent Darwin dentition derivation diverge doctrine of Descent Echinoderms embryonic Eocene exhibit external facts families fauna fish formation fossil Ganoids Gastrula genera genus geological Goethe grade gradually groups Haeckel heredity higher horse human hypothesis idea individual infer intermediate forms islands lancelet language larva larvæ likewise linguistic Linnæus lower mammals Marsupials Medusa ment merely metamorphosis modifications morphological mutability natural selection observation Oolite organisms origin peculiar pedigree perfect period phase phenomena placenta plants polypes possess present primordial progenitors races relations remains reproduction reptiles resemblance Rütimeyer says scarcely scientific separate sexual Silurian skull species sponges strata structure systematic terrestrial animals Tertiary theory of selection tion transformation transition true Ungulata Ungulates varieties vegetal vertebral column Vertebrata vertebrate animals whole
مقاطع مشهورة
الصفحة 162 - 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.18 Darwin always knew that his views would be controversial. A few days before The Origin of Species appeared, Darwin wrote, in a letter to Wallace, 'God knows what...
الصفحة 160 - I had not formerly sufficiently considered the existence of many structures which appear to be, as far as we can judge, neither beneficial nor injurious ; and this I believe to be one of the greatest oversights as yet detected in my work.
الصفحة 160 - Na'geli on plants, and the remarks by various authors with respect to animals, more especially those recently made by Professor Broca, that in the earlier editions of my Origin of Species I perhaps attributed too much to the action of natural selection or the survival of the fittest.