A NATURALIST'S VOYAGE ROUND THE WORLD; or, A
JOURNAL OF RESEARCHES into the NATURAL HISTORY and GEOLOGY of the COUNTRIES visited during the Voyage of H. M. S. Beagle, under the Command of Capt. Frrz-Ror, R. N. Post 8vo. 98.
ON THE STRUCTURE AND DISTRIBUTION OF CORAL REEFS.
GEOLOGICAL OBSERVATIONS ON VOLCANIC ISLANDS.
GEOLOGICAL OBSERVATIONS ON SOUTH AMERICA.
A MONOGRAPH OF THE CIRRIPEDIA. Illustrations. 2 vols. 8vo.
ON THE VARIOUS CONTRIVANCES BY WHICH BRITISH AND FOREIGN ORCHIDS ARE FERTILISED BY INSECTS; and on the GOOD EFFECTS of CROSSING. With Woodcuts. Post 8vo. 98. MURRAY.
ON THE MOVEMENTS and HABITS of CLIMBING PLANTS. With Woodcuts. WILLIAMS & NORGATE.
Preparing for Publication.
DOMESTIC ANIMALS AND CULTIVATED PLANTS; or, The PRINCIPLES of VARIATION, INHERITANCE, REVERSION, CROSSING, INTER- BREEDING, and SELECTION, UNDER DOMESTICATION.
LONDON: PRINTED BY W. CLOWES AND SONS, STAMFORD STREET, AND CHARING CROSS.
VARIATION UNDER DOMESTICATION.
Causes of Variability-Effects of Habit― Correlation of Growth- Inheritance-Character of Domestic Varieties-Difficulty of distinguishing between Varieties and Species-Origin of Domestic Varieties from one or more Species- Domestic Pigeons, their Differences and Origin-Principles of Selection anciently followed, their Effects-Methodical and Unconscious Selection - Unknown Origin of our Domestic Productions-Circumstances favourable to Man's power of Selection
Wide- Variability Individual differences ranging, much-diffused, and common species vary most-Spe- cies of the larger genera in each country vary more than the species of the smaller genera-Many of the species of the larger genera resemble varieties in being very closely, but unequally, related to each other, and in having restricted ranges
Its bearing on natural selection The term used in a wide sense Geometrical ratio of increase - Rapid increase of naturalised animals and plants- Nature of the checks to increase - Compe- tition universal-Effects of Climate - Protection from the number of individuals — Complex relations of all animals and plants throughout nature-Struggle for life most severe between individuals and varieties of the same species; often severe be- tween species of the same genus - The relation of organism to organism the most important of all relations
Natural Selection-its power compared with man's selection-its power on characters of trifling importance-its power at all ages and on both sexes - Sexual Selection - On the generality of inter- crosses between individuals of the same species-Circumstances favourable and unfavourable to Natural Selection, namely, in- tercrossing, isolation, number of individuals-Slow action - Extinction caused by Natural Selection - Divergence of Cha- racter, related to the diversity of inhabitants of any small area, and to naturalisation - Action of Natural Selection, through Divergence of Character and Extinction, on the descendants from a common parent-Explains the Grouping of all organic beings Advance in organisation - Low forms preserved — Objections considered Indefinite multiplication of species- Summary ..
Effects of external conditions - Use and disuse, combined with natural selection; organs of flight and of vision Acclimatisa- tion-Correlation of growth Compensation and economy of growth-False correlations - Multiple, rudimentary, and lowly organised structures variable Parts developed in an unusual manner are highly variable: specific characters more variable than generic secondary sexual characters variable - Species of the same genus vary in an analogous manner - Reversions to long-lost characters - Summary . 157-198
Difficulties on the theory of descent with modification-Transitions- Absence or rarity of transitional varieties-Transitions in habits of life-Diversified habits in the same species-Species with habits widely different from those of their allies - Organs of extreme perfection-Modes of transition-Cases of difficulty — Natura non facit saltum - Organs of small inportance - Organs not in all cases absolutely perfect -The law of Unity of Type and of the Conditions of Existence embraced by the theory of Natural Selection.. Page 199-247
Instincts comparable with habits, but different in their origin- Instincts graduated - Aphides and ants- Instincts variable- Domestic instincts, their origin — Natural instincts of the cuckoo, ostrich, and parasitic bees- Slave-making ants- Hive-bee, its cell-making instinct-Changes of instinct and structure not necessarily simultaneous - Difficulties on the theory of the Natural Selection of instincts Neuter or sterile insects. Summary
Distinction between the sterility of first crosses and of hybrids - Sterility various in degree, not universal, affected by close inter- breeding, removed by domestication-Laws governing the sterility of hybrids - Sterility not a special endowment, but incidental on other differences, not accumulated by natural selection — Causes of the sterility of first crosses and of hybrids-Parallelism between the effects of changed conditions of life and of crossing- Dimorphism and Trimorphism Fertility of varieties when crossed and of their mongrel offspring not universal — Hybrids and mongrels compared independently of their fertility- Summary.. 292-338
ON THE IMPERFECTION OF THE GEOLOGICAL RECORD.
On the absence of intermediate varieties at the present day the nature of extinct intermediate varieties; on their number- On the vast lapse of time, as inferred from the rate of deposi- tion and of denudation On the poorness of our palæontological collections - On the denudation of granitic areas - On the intermittence of geological formations - On the absence of intermediate varieties in any one formation
appearance of groups of species-On their sudden appearance in the lowest known fossiliferous strata..
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 appear- ance 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.. 376-414
GEOGRAPHICAL DISTRIBUTION.
Present distribution cannot be accounted for by differences in phy- sical conditions - Importance of barriers — Affinity of the pro- ductions 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 co-extensive with the world ..
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