Search Results - The Complete Work of Charles Darwin Online

100%

F373 Book: Darwin, C. R. 1859. On the origin of species by means of natural selection, or the preservation of favoured races in the struggle for life. London: John Murray. 1st ed., 1st issue. Text Image PDF

account for our several domestic races by this process, we must admit the former existence of the most extreme forms, as the Italian greyhound, bloodhound, bull-dog, c., in the wild state. Moreover, the possibility of making distinct races by crossing has been greatly exaggerated. There can be no doubt that a race may be modified by occasional crosses, if aided by the careful selection of those individual mongrels, which present any desired character; but that a race could be obtained nearly

99%

F373 Book: Darwin, C. R. 1859. On the origin of species by means of natural selection, or the preservation of favoured races in the struggle for life. London: John Murray. 1st ed., 1st issue. Text Image PDF

agriculturalists than almost any other individual, and who was himself a very good judge of an animal, speaks of the principle of selection as that which enables the agriculturist, not only to modify the character of his flock, but to change it altogether. It is the magician's wand, by means of which he may summon into life whatever form and mould he pleases. Lord Somerville, speaking of what breeders have done for sheep, says:— It would seem as if they had chalked out upon a wall a form perfect in

99%

F373 Book: Darwin, C. R. 1859. On the origin of species by means of natural selection, or the preservation of favoured races in the struggle for life. London: John Murray. 1st ed., 1st issue. Text Image PDF

. Seedlings destroyed by insects, 67. Seeds, nutriment in, 77. ——, winged, 146. ——, power of resisting salt-water, 358. —— in crops and intestines of birds, 361. —— eaten by fish, 362, 387. —— in mud, 386. ——, hooked, on islands, 392. Selection of domestic products, 29. ——, principle not of recent origin, 33. ——, unconscious, 34. ——, natural, 80. ——, sexual, 87. ——, natural, circumstances favourable to, 101. Sexes, relations of, 87. Sexual characters variable, 156. —— selection, 87. Sheep, Merino, their

100%

F376 Book: Darwin, C. R. 1860. On the origin of species by means of natural selection, or the preservation of favoured races in the struggle for life. London: John Murray. 2d ed., second issue. Text Image PDF

occasional crosses, if aided by the careful selection of those individual mongrels, which present any desired character; but that a race could be obtained nearly intermediate between two extremely different races or species, I can hardly believe. Sir J. Sebright expressly experimentised for this object, and failed. The offspring from the first cross between two pure breeds is tolerably and sometimes (as I have found with pigeons) extremely uniform, and everything seems simple enough; but when these

100%

F376 Book: Darwin, C. R. 1860. On the origin of species by means of natural selection, or the preservation of favoured races in the struggle for life. London: John Murray. 2d ed., second issue. Text Image PDF

agriculturists than almost any other individual, and who was himself a very good judge of an animal, speaks of the principle of selection as that which enables the agriculturist, not only to modify the character of his flock, but to change it altogether. It is the magician's wand, by means of which he may summon into life whatever form and mould he pleases. Lord Somerville, speaking of what breeders have done for sheep, says:— It would seem as if they had chalked out upon a wall a form perfect in

99%

F376 Book: Darwin, C. R. 1860. On the origin of species by means of natural selection, or the preservation of favoured races in the struggle for life. London: John Murray. 2d ed., second issue. Text Image PDF

. Seedlings destroyed by insects, 67. Seeds, nutriment in, 77. ——, winged, 146. ——, power of resisting salt-water, 358. —— in crops and intestines of birds, 361. —— eaten by fish, 362, 387. —— in mud, 386. ——, hooked, on islands, 392. Selection of domestic products, 29. ——, principle not of recent origin, 33. ——, unconscious, 34. ——, natural, 80. ——, sexual, 87. ——, natural, circumstances favourable to, 102. Sexes, relations of, 87. Sexual characters variable, 156. —— selection, 87. Sheep, Merino

100%

F381 Book: Darwin, C. R. 1861. On the origin of species by means of natural selection, or the preservation of favoured races in the struggle for life. London: John Murray. 3d ed. Seventh thousand. Text Image PDF

, bloodhound, bull-dog, c., in the wild state. Moreover, the possibility of making distinct races by crossing has been greatly exaggerated. Many cases are on record, showing that a race may be modified by occasional crosses, if aided by the careful selection of those individual mongrels which present any desired character; but that a race could be obtained nearly intermediate between two extremely different races or species, I can hardly believe. Sir J. Sebright expressly experimented for this object, and

100%

F381 Book: Darwin, C. R. 1861. On the origin of species by means of natural selection, or the preservation of favoured races in the struggle for life. London: John Murray. 3d ed. Seventh thousand. Text Image PDF

who was probably better acquainted with the works of agriculturists than almost any other individual, and who was himself a very good judge of an animal, speaks of the principle of selection as that which enables the agriculturist, not only to modify the character of his flock, but to change it altogether. It is the magician's wand, by means of which he may summon into life whatever form and mould he pleases. Lord Somerville, speaking of what breeders have done for sheep, says:— It would seem

99%

F381 Book: Darwin, C. R. 1861. On the origin of species by means of natural selection, or the preservation of favoured races in the struggle for life. London: John Murray. 3d ed. Seventh thousand. Text Image PDF

selection of sheep, 32. Saurophagus sulphuratus, 201. Schiödte on blind insects, 155. Sorbus, grafts of, 284. Schlegel on snakes, 162. Spaniel, King Charles's breed, 36. Sea-water, how far injurious to seeds, 388. Specialisation of organs, 134. Species, polymorphic, 48. Sebright, Sir J., on crossed animals, 20. ——, dominant, 56. ——, on selection of pigeons, 32. ——, common, variable, 55. Sedgwick, Prof., on groups of species suddenly appearing, 327. —— in large genera variable, 57. ——, groups of

100%

F385 Book: Darwin, C. R. 1866. On the origin of species by means of natural selection, or the preservation of favoured races in the struggle for life. London: John Murray. 4th ed. 8th thousand. Text Image PDF

races by crossing has been greatly exaggerated. Many cases are on record, showing that a race may be modified by occasional crosses, if aided by the careful selection of the individuals which present the desired character; but to obtain a race nearly intermediate between two extremely different races or species, would be very difficult. Sir J. Sebright expressly experimented for this object, and failed. The offspring from the first cross between two pure breeds is tolerably and sometimes (as I

100%

F385 Book: Darwin, C. R. 1866. On the origin of species by means of natural selection, or the preservation of favoured races in the struggle for life. London: John Murray. 4th ed. 8th thousand. Text Image PDF

ables the agriculturist, not only to modify the character of his flock, but to change it altogether. It is the magician's wand, by means of which he may summon into life whatever form and mould he pleases. Lord Somerville, speaking of what breeders have done for sheep, says: It would seem as if they had chalked out upon a wall a form perfect in itself, and then had given it existence. That most skilful breeder, Sir John Sebright, used to say, with respect to pigeons, that he would produce any

99%

F385 Book: Darwin, C. R. 1866. On the origin of species by means of natural selection, or the preservation of favoured races in the struggle for life. London: John Murray. 4th ed. 8th thousand. Text Image PDF

to seeds, 429. not destructive to land-shells, 472. Sebright, Sir J., on crossed animals, 21. , on selection of pigeons, 33. Sedgwick, Prof., on groups of species suddenly appearing, 364. Seedlings destroyed by insects, 77. Seeds, nutriment in, 88. , winged, 174. , means of dissemination, 228, 240, 432. , power of resisting salt-water, 429. , in crops and intestines of birds, 431. eaten by fish, 431, 461. in mud, 460. , hooked, on islands, 466. Selection of domestic products, 31. , principle

66%

F387 Book: Darwin, C. R. 1869. On the origin of species by means of natural selection, or the preservation of favoured races in the struggle for life. London: John Murray. 5th ed. Tenth thousand. Text Image PDF

distinct races by crossing has been greatly exaggerated. Many cases are on record, showing that a race may be modified by occasional crosses, if aided by the careful selection of the individuals which present the desired character; but to obtain a race nearly intermediate between two extremely different races or species, would be very difficult. Sir J. Sebright expressly experimented for this object, and failed. The offspring from the first cross between two pure breeds is tolerably and

66%

F387 Book: Darwin, C. R. 1869. On the origin of species by means of natural selection, or the preservation of favoured races in the struggle for life. London: John Murray. 5th ed. Tenth thousand. Text Image PDF

PLUMAGE. Plumage, laws of change in sexes of birds, 102. Plums in the United States, 98. Pointer dog, origin of, 38. , habits of, 263. Poison not affecting certain coloured animals, 13. , similar effect of, on animals and plants, 572. Pollen of fir-trees, 249. transported by various means, 235, 246. Poole, Col., on striped hemionus, 199. Potamogeton, 466. Prestwich, Mr., on English and French eocene formations, 401. Proctotrupes, 221. Proteolepas, 183. Proteus, 174. Psychology, future progress