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Capítol X. On the Imperfection of the Geological Record. | |
| On the absence of intermediate varieties at the present day — On the nature of extinct intermediate varieties; on their number — On the lapse of time, as inferred from the rate of denudation and of deposition — On the lapse of time as estimated by years — On the poorness of our palæontological collections — On the intermittence of geological formations — On the denudation of granitic areas — On the absence of intermediate varieties in any one formation — On the sudden appearance of groups of species — On their sudden appearance in the lowest known fossiliferous strata — Antiquity of the habitable earth | 264-289 |
Capítol XI. On the Geological Succession of Organic Beings. | |
| On the slow and successive appearance of new species — On their different rates of change — Species once lost do not reappear — Groups of species follow the same general rules in their appearance and disappearance as do single species — On Extinction — On simultaneous changes in the forms of life throughout the world — On the affinities of extinct species to each other and to living species — On the state of development of ancient forms — On the succession of the same types within the same areas — Summary of preceding and present chapter | 290-315 |
Capítol XII. Geographical Distribution. | |
| Present distribution cannot be accounted for by differences in physical conditions — Importance of barriers — Affinity of the productions of the same continent — Centres of creation — Means of dispersal, by changes of climate and of the level of the land, and by occasional means — Dispersal during the Glacial period — Alternate Glacial periods in the north and south | 316-342 |
Capítol XIII. Geographical Distribution—continued. | |
| Distribution of fresh-water productions — On the inhabitants of oceanic islands — Absence of Batrachians and of terrestrial Mammals — On the relation of the inhabitants of islands to those of the nearest mainland — On colonization from the nearest source with subsequent modification — Summary of the last and present chapter | 343-362
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