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A331    Book:     Poulton, Edward Bagnall. 1909. Charles Darwin and the Origin of species: addresses, etc., in America and England in the year of the two anniversaries. London: Longmans, Green, and Co.   Text   Image
. Araschnia levana, mimicking Limenitis, 176. Archaeopteryx, discussed at Brit. Assoc. (1881), 29, 30. archippus, Limenitis, 137, 155, 161, 164-72, 176, 186-8, 191, 199, 204-5; evolution of mimicry in, 164-8; stripeless var. at Albany, 166 n. 2, 211-12. arctic alpine forms, 123, 123 n. 2 . Arctiidae, as mimics, 121. Argyll, Duke of, on natural selection, 44; criticisms by, 251-3; Darwin to, 251-2. Argynnis diana, female of mimics, L. astyattax, 189, 207. niphe, female of mimics, D. chrysippus, 161
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A331    Book:     Poulton, Edward Bagnall. 1909. Charles Darwin and the Origin of species: addresses, etc., in America and England in the year of the two anniversaries. London: Longmans, Green, and Co.   Text   Image
, J. S. Duncan (in work of P. B. Duncan), 95-6. Caterpillars, warning colours of, 111, 112. Catskill Mountains, 211. Centres of creation, 248-9. Cethosia, mimicry in, 133, 136, 161. Ceylon, 157. Chalk, continuous evolution in the white, 280 n. 1. Challenger, 256. Chambers, R., 15. chamaeleon, Achaea, 224 n. 1. Chameleon, W. J. Burchell on, 97; Lloyd Morgan on, 97; colour of, adjustable on two sides independently, 109, 110. Charles Darwin and the Theory of Natural Selection, Poulton, 126, 129
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A331    Book:     Poulton, Edward Bagnall. 1909. Charles Darwin and the Origin of species: addresses, etc., in America and England in the year of the two anniversaries. London: Longmans, Green, and Co.   Text   Image
Weismann of, 39-40. continuous or discontinuous evolution, 48-51; mimicry and, 138-9, 14 7-8, 200, 208; fossils of the white chalk and, 280 n. 1. Cook, J. H., on stripeless L. archippus, 166 n. 2, 210-12; lanthanis var. named by Watson and, 212. Cope, E. D., American Palaeontology and, 2. Coprid beetles as mimics, 120-1. Coral islands, Darwin's theory of, 75; supported by A. Agassiz, 2; confirmed, 45. Cordilleras, 34. Cornhill Mag., 73. cornuta, Disa, 220 n. 1. Cosmodesmus, both sexes of
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A331    Book:     Poulton, Edward Bagnall. 1909. Charles Darwin and the Origin of species: addresses, etc., in America and England in the year of the two anniversaries. London: Longmans, Green, and Co.   Text   Image
'continuous' evolution in the white chalk, 280 n. 1. Royal Institution, 67. Royal Society of Edinburgh, Proc. of, 19, 44. Royal Society, Phil. Trans. of, 101. Rugby School Nat. Hist. Soc., 109. S. America, Darwin and Wallace in, 1; thorn-bearing plants of, 98; n. forms m S. of, 46; butterfly models of, 153-4; invaded by Danaida from N., 163-4, 204. Salatura, see Danaida decipiens, genutia, and insolata. Salisbury Lord, D.C.L. offered to Darwin in 1870 by, 90. Sargassum resembled by Scyllaea, 107, 108
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A331    Book:     Poulton, Edward Bagnall. 1909. Charles Darwin and the Origin of species: addresses, etc., in America and England in the year of the two anniversaries. London: Longmans, Green, and Co.   Text   Image
. Strelitzia reginae, fertilized by sun-bird, 217, 228-9, 228 n. 2. strigosa, f. of Danaida berenice, 154, 162-4, 171-2, 204-5. struggle for existence, the essential feature of Darwinism, 8, 9; rate of evolution determined by, 46-7; adaptation, natural selection and, 94-101. sublime, feelings of the, 34-7. Sugar-bird, see 'sun-bird'. Sun-bird, Strelitzia fertilized by, 228-9, 228 n. 2. [page] 300 INDE
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A331    Book:     Poulton, Edward Bagnall. 1909. Charles Darwin and the Origin of species: addresses, etc., in America and England in the year of the two anniversaries. London: Longmans, Green, and Co.   Text   Image
Sybilla, Limenitis, 164. Sydney, 202. 'Tails' of Pharmacophagus, primitive, 181. tanager, scarlet, 142. Tasitia, see 'Danaida 'berenice' and 'D. strigosa'. Tasmanian insects of Beagle, 202. Teleology and adaptation, 94-8. Telephoridae as mimics, 120. Tendrils, Darwin on origin of, 73-4. Tennyson, natural selection and, 8, 9. Thackeray, F. St. J., on Tennyson and evolution, 9 n. 1. Thayer, A. H., on white under sides of animal, 109, 110. Thiselton-Dyer, Sir William, 234 n. 2; at Oxford
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F1481    Book:     Anon. 1909. Order of the proceedings at the Darwin celebrations held at Cambridge June 22-June 24, 1909. With a sketch of Darwin's life. Cambridge: University Press.   Text   Image   PDF
working for the next twenty years. ...Had been greatly struck from about month of previous March on character of South American fossils, and species on Galapagos Archipelago. These facts origin (especially latter) of all my views. 1 On the question of when Darwin's mind was first turned towards Evolution, see Professor Judd in Darwin and Modern Science (Cambridge, 1909), also the introduction to The Foundations of the Origin of Species. [page] 1
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A162    Book:     Seward, A. C. ed. 1909. Darwin and modern science. Essays in commemoration of the centenary of the birth of Charles Darwin and of the fiftieth anniversary of the publication of The origin of species. Cambridge: Cambridge University Press.   Text   Image   PDF
Therefore, as far more important than any further ferreting out of vague hints of Natural Selection in books which Darwin never read, we would indicate by a quotation the view that the central idea in Darwinism is correlated with contemporary social evolution. The substitution of Darwin for Paley as the chief interpreter of the order of nature is currently regarded as the displacement of an anthropomorphic view by a purely scientific one: a little reflection, however, will show that what has
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A162    Book:     Seward, A. C. ed. 1909. Darwin and modern science. Essays in commemoration of the centenary of the birth of Charles Darwin and of the fiftieth anniversary of the publication of The origin of species. Cambridge: Cambridge University Press.   Text   Image   PDF
century, but by his own observations, so it was in regard to the principle of selection. He was struck by the innumerable cases of adaptation, as, for instance, that of the woodpeckers and tree-frogs to climbing, or the hooks and feather-like appendages of seeds, which aid in the distribution of plants, and he said to himself that an explanation of adaptations was the first thing to be sought for in attempting to formulate a theory of evolution. But since adaptations point to changes which
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A162    Book:     Seward, A. C. ed. 1909. Darwin and modern science. Essays in commemoration of the centenary of the birth of Charles Darwin and of the fiftieth anniversary of the publication of The origin of species. Cambridge: Cambridge University Press.   Text   Image   PDF
attended its evolution. Of the six young brought forth by a pair of elephants in the course of their lives only two survive in a given area; similarly, of the millions of eggs which two thread-worms leave behind them only two survive. It is thus possible to estimate the dangers which threaten a species by its ratio of elimination, or, since this cannot be done directly, by its fertility. Although a great number of the descendants of each generation fall victims to accident, among those that remain it
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A162    Book:     Seward, A. C. ed. 1909. Darwin and modern science. Essays in commemoration of the centenary of the birth of Charles Darwin and of the fiftieth anniversary of the publication of The origin of species. Cambridge: Cambridge University Press.   Text   Image   PDF
minute steps, which, if useful, 1 Vortr ge ber Descendenztheorie, Jena, 1904, II. 269. Eng. Transl. London, 1904, II. p. 317. 2 See Poulton, Essays on Evolution, Oxford, 1908, pages xix-xxii. 3 Origin of Species (6th edit.), pp. 176 et seq. [page] 2
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A162    Book:     Seward, A. C. ed. 1909. Darwin and modern science. Essays in commemoration of the centenary of the birth of Charles Darwin and of the fiftieth anniversary of the publication of The origin of species. Cambridge: Cambridge University Press.   Text   Image   PDF
need only draw the conclusion that one and the same caterpillar may exhibit the initial stages of both, and that it depends on the manner in which these marking elements are intensified and combined by natural selection whether whitish longitudinal or oblique stripes should result. In this case then the useful variations were actually always there, and we see that in the same group of Lepidoptera, e.g. species of Sphingidae, evolution has occurred in both directions according to whether the
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A162    Book:     Seward, A. C. ed. 1909. Darwin and modern science. Essays in commemoration of the centenary of the birth of Charles Darwin and of the fiftieth anniversary of the publication of The origin of species. Cambridge: Cambridge University Press.   Text   Image   PDF
to weigh down the animal altogether. It is inconceivable, he says, that so many processes of selection should take place simultaneously, and we are therefore forced to fall back on the Lamarckian factor of the use and disuse of functional parts. And how, he asks, could natural selection follow two opposite directions of evolution in different parts of the body at the same time, as for instance in the case of the kangaroo, in which the forelegs must have become shorter, while the hind legs and
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A162    Book:     Seward, A. C. ed. 1909. Darwin and modern science. Essays in commemoration of the centenary of the birth of Charles Darwin and of the fiftieth anniversary of the publication of The origin of species. Cambridge: Cambridge University Press.   Text   Image   PDF
enemies. Wallace was the first to point out that in species with concealed nests the beautiful feathers of the male occurred in the female also, as in the parrots, for instance, but this is not the case in species which brood on an exposed nest. In the parrots one can often observe that the general brilliant colouring of the male is found 1 The Evolution Theory, London, 1904, I. p. 219. [page] 4
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A162    Book:     Seward, A. C. ed. 1909. Darwin and modern science. Essays in commemoration of the centenary of the birth of Charles Darwin and of the fiftieth anniversary of the publication of The origin of species. Cambridge: Cambridge University Press.   Text   Image   PDF
mimetic palatable forms—confirm it in the most convincing manner. Of the many cases now known I select 1 Essays on Evolution, 1889-1907, Oxford, 1908, passim, e.g. p. 269. 2 The expression does not refer to all the enemies of this butterfly; against ichneumon-flies, for instance, their unpleasant smell usually gives no protection. [page] 5
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A162    Book:     Seward, A. C. ed. 1909. Darwin and modern science. Essays in commemoration of the centenary of the birth of Charles Darwin and of the fiftieth anniversary of the publication of The origin of species. Cambridge: Cambridge University Press.   Text   Image   PDF
. Anyone who is interested in the matter will find a full and exact statement of the case in as far as we know it, in Poulton's Essays on Evolution (pp. 373-3751). I need only add that three different mimetic female forms have been reared from the eggs of a single female in South Africa. The resemblance of these forms to their immune models goes so far that even the details of the local forms of the models are copied by the mimetic species. It remains to be said that in Madagascar a butterfly
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A162    Book:     Seward, A. C. ed. 1909. Darwin and modern science. Essays in commemoration of the centenary of the birth of Charles Darwin and of the fiftieth anniversary of the publication of The origin of species. Cambridge: Cambridge University Press.   Text   Image   PDF
animal, the disappearance of the ear-muscles and the auditory passages, the displacement of the external nares to the forehead for the greater security of the breathing-hole during the brief appearance at the surface, and certain remarkable changes in the respiratory and circulatory organs which enable the animal to remain for a long time 1 The Evolution Theory, London, 1904, p. 144. [page] 6
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A162    Book:     Seward, A. C. ed. 1909. Darwin and modern science. Essays in commemoration of the centenary of the birth of Charles Darwin and of the fiftieth anniversary of the publication of The origin of species. Cambridge: Cambridge University Press.   Text   Image   PDF
first arise through selection in the course of the evolution of the birds, for it formed the covering of the scales of their reptilian ancestors. It is quite true that a similar substance covered the scales of the Reptiles, but why should it not have arisen among them through selection? Or in what other way could it have arisen, since scales are also passively useful parts? It is true that if we are only to call adaptation what has been acquired by the species we happen to be considering, there
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A162    Book:     Seward, A. C. ed. 1909. Darwin and modern science. Essays in commemoration of the centenary of the birth of Charles Darwin and of the fiftieth anniversary of the publication of The origin of species. Cambridge: Cambridge University Press.   Text   Image   PDF
modifications. These have been of paramount importance on many lines of evolution of the animal as well as of the vegetable kingdom. It is often assumed that monocotyledons are descended from some lower group of dicotyledons, probably allied to that which includes the buttercup family. On this view the monocotyledons must be assumed to have lost the cambium and all its influence on secondary growth, the differentiation of the flower into calyx and corolla, the second cotyledon or seed-leaf and
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A162    Book:     Seward, A. C. ed. 1909. Darwin and modern science. Essays in commemoration of the centenary of the birth of Charles Darwin and of the fiftieth anniversary of the publication of The origin of species. Cambridge: Cambridge University Press.   Text   Image   PDF
such views had been promulgated; and many must, as Huxley says, have taken up his own position of critical expectancy1. Why, then, was it, that Darwin succeeded where the rest had failed? The cause of that success was two-fold. First, and obviously, in the principle of Natural Selection he had a suggestion which would work. It might not go the whole way, but it was true as far as it went. Evolution could thus in great measure be fairly represented as a consequence of demonstrable processes
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