Search Results - The Complete Work of Charles Darwin Online

77%

F401 Book: Darwin, C. R. 1876. The origin of species by means of natural selection, or the preservation of favoured races in the struggle for life. London: John Murray. 6th ed., with additions and corrections. [First issue of final definitive text] Text Image PDF

having affinities directed towards very distinct groups. Yet if we compare the older Reptiles and Batrachians, the older Fish, the older Cephalopods, and the eocene Mammals, with the more recent members of the same classes, we must admit that there is truth in the remark. Let us see how far these several facts and inferences accord with the theory of descent with modification. As the subject is somewhat complex, I must request the reader to turn to the diagram in the fourth chapter. We may suppose

76%

F401 Book: Darwin, C. R. 1876. The origin of species by means of natural selection, or the preservation of favoured races in the struggle for life. London: John Murray. 6th ed., with additions and corrections. [First issue of final definitive text] Text Image PDF

CHAPTER VI. DIFFICULTIES OF THE THEORY. Difficulties of the theory of descent with modification 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 importance Organs not in all cases absolutely perfect The law of Unity of Type and of the Conditions of Existence

76%

F401 Book: Darwin, C. R. 1876. The origin of species by means of natural selection, or the preservation of favoured races in the struggle for life. London: John Murray. 6th ed., with additions and corrections. [First issue of final definitive text] Text Image PDF

where our oscillating continents now stand they have stood since the commencement of the Cambrian system; but that, long before that epoch, the world presented a widely different aspect; and that the older continents, formed of formations older than any known to us, exist now only as remnants in a metamorphosed condition, or lie still buried under the ocean. Passing from these difficulties, the other great leading facts in pal ontology agree admirably with the theory of descent with

76%

F401 Book: Darwin, C. R. 1876. The origin of species by means of natural selection, or the preservation of favoured races in the struggle for life. London: John Murray. 6th ed., with additions and corrections. [First issue of final definitive text] Text Image PDF

with modification 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 importance 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 133-167 [page] vi

75%

F401 Book: Darwin, C. R. 1876. The origin of species by means of natural selection, or the preservation of favoured races in the struggle for life. London: John Murray. 6th ed., with additions and corrections. [First issue of final definitive text] Text Image PDF

without any thought on the subject, these tumblers are kept in the same group, because allied in blood and alike in some other respects. With species in a state of nature, every naturalist has in fact brought descent into his classification; for he includes in his lowest grade, that of species, the two sexes; and how enormously these sometimes differ in the most important characters, is known to every naturalist: scarcely a single fact can be predicated in common of the adult males and

75%

F401 Book: Darwin, C. R. 1876. The origin of species by means of natural selection, or the preservation of favoured races in the struggle for life. London: John Murray. 6th ed., with additions and corrections. [First issue of final definitive text] Text Image PDF

, who has drawn an important distinction between certain classes of cases which have all been equally ranked by naturalists as homologous. He proposes to call the structures which resemble each other in distinct animals, owing to their descent from a common progenitor with subsequent modification, homogenous; and the resemblances which cannot thus be accounted for, he proposes to call homoplastic. For instance, he believes that the hearts of birds and mammals are as a whole homogenous, that is

75%

F401 Book: Darwin, C. R. 1876. The origin of species by means of natural selection, or the preservation of favoured races in the struggle for life. London: John Murray. 6th ed., with additions and corrections. [First issue of final definitive text] Text Image PDF

are, in my judgment they are by no means sufficient to overthrow the theory of descent with subsequent modification. Now let us turn to the other side of the argument. Under domestication we see much variability, caused, or at least excited, by changed conditions of life; but often in so obscure a manner, that we are tempted to consider the variations as spontaneous. Variability is governed by many complex laws, by correlated growth, compensation, the increased use and disuse of parts, and the

75%

F401 Book: Darwin, C. R. 1876. The origin of species by means of natural selection, or the preservation of favoured races in the struggle for life. London: John Murray. 6th ed., with additions and corrections. [First issue of final definitive text] Text Image PDF

CHAPTER XIV. Mutual Affinities of Organic Beings: Morphology: Embryology: Rudimentary Organs. Classification, groups subordinate to groups Natural system Rules and difficulties in classification, explained on the theory of descent with modification Classification of varieties Descent always used in classification Analogical or adaptive characters Affinities, general, complex, and radiating Extinction separates and defines groups Morphology, between members of the same class, between parts of

74%

F401 Book: Darwin, C. R. 1876. The origin of species by means of natural selection, or the preservation of favoured races in the struggle for life. London: John Murray. 6th ed., with additions and corrections. [First issue of final definitive text] Text Image PDF

Silurian genera. So that the comparative value of the differences between these organic beings, which are all related to each other in the same degree in blood, has come to be widely different. Nevertheless their genealogical arrangement remains strictly true, not only at the present time, but at each successive period of descent. All the modified descendants from A will have inherited something in common from their common parent, as will all the descendants from I; so will it be with each

72%

F401 Book: Darwin, C. R. 1876. The origin of species by means of natural selection, or the preservation of favoured races in the struggle for life. London: John Murray. 6th ed., with additions and corrections. [First issue of final definitive text] Text Image PDF

difficulties, but it does not accord with all the facts in regard to the productions of islands. In the following remarks I shall not confine myself to the mere question of dispersal, but shall consider some other cases bearing on the truth of the two theories of independent creation and of descent with modification. The species of all kinds which inhabit oceanic islands are few in number compared with those on equal continental areas: Alph. de Candolle admits this for plants, and Wollaston for

71%

F401 Book: Darwin, C. R. 1876. The origin of species by means of natural selection, or the preservation of favoured races in the struggle for life. London: John Murray. 6th ed., with additions and corrections. [First issue of final definitive text] Text Image PDF

('Bulletins de l'Acad. Roy. Bruxelles, tom. xiii. p. 581), his opinion that it is more probable that new species have been produced by descent with modification than that they have been separately created: the author first promulgated this opinion in 1831. Professor Owen, in 1849 ('Nature of Limbs,' p. 86), wrote as follows: The archetypal idea was manifested in the flesh under diverse such modifications, upon this planet, long prior to the existence of those animal species that actually exemplify

70%

F401 Book: Darwin, C. R. 1876. The origin of species by means of natural selection, or the preservation of favoured races in the struggle for life. London: John Murray. 6th ed., with additions and corrections. [First issue of final definitive text] Text Image PDF

briefly recapitulated. That many and serious objections may be advanced against the theory of descent with modification through variation and natural selection, I do not deny. I have endeavoured to give to them their full force. Nothing at first can appear more difficult to believe than that the more complex organs and instincts have been perfected, not by means superior to, though analogous with, human reason, but by the accumulation of innumerable slight variations, each good for the individual

70%

F401 Book: Darwin, C. R. 1876. The origin of species by means of natural selection, or the preservation of favoured races in the struggle for life. London: John Murray. 6th ed., with additions and corrections. [First issue of final definitive text] Text Image PDF

The similar framework of bones in the hand of a man, wing of a bat, fin of the porpoise, and leg of the horse, the same number of vertebr forming the neck of the giraffe and of the elephant, and innumerable other such facts, at once explain themselves on the theory of descent with slow and slight successive modifications. The similarity of pattern in the wing and in the leg of a bat, though used for such different purpose, in the jaws and legs of a crab, in the petals, stamens, and pistils of

70%

F401 Book: Darwin, C. R. 1876. The origin of species by means of natural selection, or the preservation of favoured races in the struggle for life. London: John Murray. 6th ed., with additions and corrections. [First issue of final definitive text] Text Image PDF

(I), and the eight descended from (A), will have to be ranked as very distinct genera, or even as distinct sub-families. Thus it is, as I believe, that two or more genera are produced by descent with modification, from two or more species of the same genus. And the two or more parent-species are supposed to be descended from some one species of an earlier genus. In our diagram, this is indicated by the broken lines, beneath the capital letters, converging in sub-branches downwards towards a

70%

F401 Book: Darwin, C. R. 1876. The origin of species by means of natural selection, or the preservation of favoured races in the struggle for life. London: John Murray. 6th ed., with additions and corrections. [First issue of final definitive text] Text Image PDF

creation. The term variety is almost equally difficult to define; but here community of descent is almost universally implied, though it can rarely be proved. We have also what are called monstrosities; but they graduate into varieties. By a monstrosity I presume is meant some considerable deviation of structure, generally injurious, or not useful to the species. Some authors use the term variation in a technical sense, as implying a modification directly due to the physical conditions of life

70%

F401 Book: Darwin, C. R. 1876. The origin of species by means of natural selection, or the preservation of favoured races in the struggle for life. London: John Murray. 6th ed., with additions and corrections. [First issue of final definitive text] Text Image PDF

original parent-species itself, will generally tend to become extinct. So it probably will be with many whole collateral lines of descent, which will be conquered by later and improved lines. If, however, the modified offspring of a species get into some distinct country, or become quickly adapted to some [page] 9

67%

F401 Book: Darwin, C. R. 1876. The origin of species by means of natural selection, or the preservation of favoured races in the struggle for life. London: John Murray. 6th ed., with additions and corrections. [First issue of final definitive text] Text Image PDF

resemblance. I believe that this is the case, and that community of descent the one known cause of close similarity in organic beings is the bond, which though observed by various degrees of modification, is partially revealed to us by our classifications. Let us now consider the rules followed in classification, and the difficulties which are encountered on the view that classification either gives some unknown plan of creation, or is simply a scheme for enunciating general propositions and of placing

66%

F401 Book: Darwin, C. R. 1876. The origin of species by means of natural selection, or the preservation of favoured races in the struggle for life. London: John Murray. 6th ed., with additions and corrections. [First issue of final definitive text] Text Image PDF

rudimentary nails on the fin of the manatee have been developed for this same purpose. On the view of descent with modification, the origin of rudimentary organs is comparatively simple; and we can understand to a large extent the laws governing their imperfect development. We have plenty of cases of rudimentary organs in our domestic productions, as the stump of a tail in tailless breeds, the vestige of an ear in earless breeds of sheep, the reappearance of minute dangling horns in hornless

66%

F401 Book: Darwin, C. R. 1876. The origin of species by means of natural selection, or the preservation of favoured races in the struggle for life. London: John Murray. 6th ed., with additions and corrections. [First issue of final definitive text] Text Image PDF

same time be able to give a definite answer to the question why two distinct species, when crossed, as well as their hybrid offspring, are generally rendered more or less sterile, whilst two domesticated varieties when crossed and their mongrel offspring are perfectly fertile. Turning to geographical distribution, the difficulties encountered on the theory of descent with modification are serious enough. All the individuals of the same species, and all the species of the same genus, or even higher

66%

F401 Book: Darwin, C. R. 1876. The origin of species by means of natural selection, or the preservation of favoured races in the struggle for life. London: John Murray. 6th ed., with additions and corrections. [First issue of final definitive text] Text Image PDF

formerly more closely allied, than it is at present, to the northern half. In a similar manner we know, from Falconer and Cautley's discoveries, that Northern India was formerly more closely related in its mammals to Africa than it is at the present time. Analogous facts could be given in relation to the distribution of marine animals. On the theory of descent with modification, the great law of the long enduring, but not immutable, succession of the same types within the same areas, is at once

95%

F801 Book: Darwin, C. R. 1877. The various contrivances by which orchids are fertilised by insects. London: John Murray. 2d ed. Text Image PDF

plan; that he, therefore, made the same organ to perform diverse functions often of trifling importance compared with their proper function converted other organs into mere purposeless rudiments, and arranged all as if they had to stand separate, and then made them cohere? Is it not a more simple and intelligible view that all the Orchide owe what they have in common, to descent from some monocotyledonous plant, which, like so many other plants of the same class, possessed fifteen organs

71%

F948 Book: Darwin, C. R. 1877. The descent of man, and selection in relation to sex. Twelfth thousand, revised and augmented. (final text). London: John Murray. Text PDF

, apart from the co-descendants of any other form; but if the parent-forms are related, so will be their descendants, and the two groups together will form a larger group. The amount of difference between the several groups—that is the amount of modification which each has undergone—is expressed by such terms as genera, families, orders, and classes. As we have no record of the lines of descent, the pedigree can be discovered only by observing the degrees of resemblance between the beings which are

67%

F948 Book: Darwin, C. R. 1877. The descent of man, and selection in relation to sex. Twelfth thousand, revised and augmented. (final text). London: John Murray. Text PDF

differences in some few points,—that is, to the amount of modification undergone; and how much to close resemblance in numerous unimportant points, as indicating the lines of descent or genealogy. To attach much weight to the few but strong differences is the most obvious and perhaps the safest course, though it appears more correct to pay great attention to the many small resemblances, as giving a truly natural classification. In forming a judgment on this head with reference to man, we must

66%

F948 Book: Darwin, C. R. 1877. The descent of man, and selection in relation to sex. Twelfth thousand, revised and augmented. (final text). London: John Murray. Text PDF

unimportant points. The greater number of naturalists who have taken into consideration the whole structure of man, including his mental faculties, have followed Blumenbach and Cuvier, and have placed man in a separate Order, under the title of the Bimana, and therefore on an equality with the orders of the Quadrumana, Carnivora, c. Recently many of our best naturalists have recurred to the view first propounded by Linnæus, so remarkable for his sagacity, and have placed man in the same Order with the

65%

F948 Book: Darwin, C. R. 1877. The descent of man, and selection in relation to sex. Twelfth thousand, revised and augmented. (final text). London: John Murray. Text PDF

sex alone, may be grouped. Rules of this kind were first enounced by Cuvier; but with the progress of knowledge they require some modification and amplification. This I have attempted to do, as far as the extreme complexity of the subject permits, from information derived from various sources; but a full essay on this subject by some competent ornithologist is much needed. In order to ascertain 1 In regard to thrushes, shrikes, and woodpeckers, see Mr. Blyth, in Charlesworth's 'Mag. of Nat. Hist

83%

F3396 Book contribution: Darwin, C. R. 1884. [Letter extract from 1881 and recollection of Darwin's words]. In R. Meldola, The presidential address: Darwin and modern evolution. Transactions of the Essex Field Club 3: 64-93. Text

based, as previously stated, upon certain indisputable facts, viz., the high rate of multiplication of living beings, the struggle for existence, change of environment, and the principle of heredity. Every species is, on this view, genetically descended from some previously existing species; and since the changes of external conditions take place on the whole with extreme slowness, the process of modification must have proceeded with corresponding slowness. It is of the utmost importance to

65%

F3396 Book contribution: Darwin, C. R. 1884. [Letter extract from 1881 and recollection of Darwin's words]. In R. Meldola, The presidential address: Darwin and modern evolution. Transactions of the Essex Field Club 3: 64-93. Text

are formed on the same pattern, and at a very early age the embryos closely resemble each other therefore I cannot doubt that the theory of descent with modification embraces all the members of the same [page] 9

62%

F1795 Periodical contribution: Darwin, C. R. 1881. Inheritance. Nature. A Weekly Illustrated Journal of Science 24 (21 July): 257. Text Image PDF

remarkable case of the transmitted effects on the brain from an injury to a nerve; but I do not feel at liberty to give this case, as Mr Dupuy intends to pursue his researches, and will, as I hope, publish the results. CHARLES DARWIN July 13 1 There are numerous references to 'inheritance at corresponding ages' in Origin, Variation and Descent. See the annotated letter in Correspondence vol. 29, pp. 312-14. 2 Origin p. 448 ff. 3 Irving Prescott Bishop (1849-1913), American school science

95%

F803 Book: Darwin, C. R. 1882. The various contrivances by which orchids are fertilised by insects. 2nd ed. Revised 3d thousand. London: John Murray. Text Image PDF

plan; that he, therefore, made the same organ to perform diverse functions often of trifling importance compared with their proper function converted other organs into mere purposeless rudiments, and arranged all as if they had to stand separate, and then made them cohere? Is it not a more simple and intelligible view that all the Orchide owe what they have in common, to descent from some monocotyledonous plant, which, like so many other plants of the same class, possessed fifteen organs

71%

F955 Book: Darwin, C. R. 1882. The descent of man, and selection in relation to sex. London: John Murray. 2d ed., fifteenth thousand. Text Image PDF

, apart from the co-descendants of any other form; but if the parent-forms are related, so will be their descendants, and the two groups together will form a larger group. The amount of difference between the several groups—that is the amount of modification which each has undergone—is expressed by such terms as genera, families, orders, and classes. As we have no record of the lines of descent, the pedigree can be discovered only by observing the degrees of resemblance between the beings which are

67%

F955 Book: Darwin, C. R. 1882. The descent of man, and selection in relation to sex. London: John Murray. 2d ed., fifteenth thousand. Text Image PDF

differences in some few points,—that is, to the amount of modification undergone; and how much to close resemblance in numerous unimportant points, as indicating the lines of descent or genealogy. To attach much weight to the few but strong differences is the most obvious and perhaps the safest course, though it appears more correct to pay great attention to the many small resemblances, as giving a truly natural classification. In forming a judgment on this head with reference to man, we must

66%

F955 Book: Darwin, C. R. 1882. The descent of man, and selection in relation to sex. London: John Murray. 2d ed., fifteenth thousand. Text Image PDF

unimportant points. The greater number of naturalists who have taken into consideration the whole structure of man, including his mental faculties, have followed Blumenbach and Cuvier, and have placed man in a separate Order, under the title of the Bimana, and therefore on an equality with the orders of the Quadrumana, Carnivora, c. Recently many of our best naturalists have recurred to the view first propounded by Linnæus, so remarkable for his sagacity, and have placed man in the same Order with the

65%

F955 Book: Darwin, C. R. 1882. The descent of man, and selection in relation to sex. London: John Murray. 2d ed., fifteenth thousand. Text Image PDF

sex alone, may be grouped. Rules of this kind were first enounced by Cuvier; but with the progress of knowledge they require some modification and amplification. This I have attempted to do, as far as the extreme complexity of the subject permits, from information derived from various sources; but a full essay on this subject by some competent ornithologist is much needed. In order to ascertain 1 In regard to thrushes, shrikes, and woodpeckers, see Mr. Blyth, in Charlesworth's 'Mag. of Nat. Hist

59%

F1434 Book contribution: Darwin, C. R. 1883. A posthumous essay on instinct. In Romanes, G. J., Mental evolution in animals. With a posthumous essay on instinct by Charles Darwin. London: Kegan Paul Trench & Co., pp. 188-189, 196, 198-199, 355-384. Text Image PDF

differences to subsequent modification through natural selection. So when we hear that the thrush of South America (T. Falklandicus), like our European species, lines her nest in the same peculiar way with mud, though, from being surrounded by wholly different plants and animals, she must be placed under somewhat different conditions; or when we hear that in North America the males of the kitty wrens,† like the male of our species, have the strange and anomalous habit of making cock-nests, not lined

60%

F1804 Periodical contribution: Darwin, C. R. 1883. The late Mr. Darwin on instinct. Nature. A Weekly Illustrated Journal of Science 29 (6 December): 128-129. Text Image PDF

instinctive action may lead to results which fill the mind with astonishment. Moreover, it seems to me that the very general fact of the gradation of complexity of instincts within the limits of the same group of animals; and likewise the fact of two allied species, placed in two distant parts of the world and surrounded by wholly different conditions of life, still having very much in common in their instincts, supports our theory of descent; for they are explained by it: whereas if we look at each

73%

F1452.2 Book: Darwin, Francis ed. 1887. The life and letters of Charles Darwin, including an autobiographical chapter. vol. 2. London: John Murray. Text Image PDF

Gray in the 'Atlantic.' It comes out very clearly that in the case of such publications as Dr. Gray's, my father did not rejoice over the success of his special view of Evolution, viz that modification is mainly due to Natural Selection; on the contrary, he felt strongly that the really important point was that the doctrine of Descent should be accepted. Thus he wrote to Professor Gray (May 11, 1863), with reference to Lyell's 'Antiquity of Man': You speak of Lyell as a judge; now what I complain

67%

F1452.2 Book: Darwin, Francis ed. 1887. The life and letters of Charles Darwin, including an autobiographical chapter. vol. 2. London: John Murray. Text Image PDF

modification implies divergence, and we become so habituated to a belief in descent, and therefore in divergence, that we do not notice the absence of proof that divergence is in itself an advantage. As shown in the Autobiography, my father in 1876 found it hardly credible that he should have overlooked the problem and its solution. The following letter will be more in place here than its chronological position, since it shows what was my father's feeling as to the value of the Sketch at the

67%

F1452.2 Book: Darwin, Francis ed. 1887. The life and letters of Charles Darwin, including an autobiographical chapter. vol. 2. London: John Murray. Text Image PDF

nearly a convert to my views. . Let me add I fully admit that there are very many difficulties not satisfactorily explained by my theory of descent with modification, but I cannot possibly believe that a false theory would explain so many classes of facts as I think it certainly does explain. On these grounds I drop my anchor, and believe that the difficulties will slowly disappear. C. Darwin to J. S. Henslow. Down, November 11th, 1859. MY DEAR HENSLOW, I have told Murray to send a copy of my book

66%

F1452.3 Book: Darwin, Francis ed. 1887. The life and letters of Charles Darwin, including an autobiographical chapter. vol. 3. London: John Murray. Text Image PDF

DESCENT. 139; in the Times, iii. 139; in the Saturday Review, iii. 139; in the 'Quarterly Review,' iii. 146. Descent with modification, primary importance of the doctrine of, ii. 371. Descriptive work, blunting effect of, ii. 379. Design in Nature, i. 315, iii. 353, 373, 377, 378, 382; argument from, as to existence of God, i. 309. , evidence of, ii. 312. Devonian strata, insect with stridulating apparatus in the, iii. 97. Devonshire caverns, pre-glacial remains in, ii. 365. 'Dichogamy' of C

64%

F1452.2 Book: Darwin, Francis ed. 1887. The life and letters of Charles Darwin, including an autobiographical chapter. vol. 2. London: John Murray. Text Image PDF

really good judges have remarked to me how desirable it would be that this should be exemplified and worked out in some detail and with some single group of beings. Now every one will admit that no one in the world could do this better than you with Brachiopods. The result might turn out very unfavourable to the views which I hold; if so, so much the better for those who are opposed to me. But I am inclined to suspect that on the whole it would be favourable to the notion of descent with

63%

F1452.2 Book: Darwin, Francis ed. 1887. The life and letters of Charles Darwin, including an autobiographical chapter. vol. 2. London: John Murray. Text Image PDF

he would see that genealogy by itself does not give classification; I declare I cannot see a much closer approach to Wallace and me in Naudin than in Lamarck we all agree in modification and descent. If I do not hear from you I will return the 'Revue' in a few days (with the cover). I dare say Lyell would be glad to see it. By the way, I will retain the volume till I hear whether I shall or not send it to Lyell. I should rather like Lyell to see this note, though it is foolish work sticking up

63%

F1452.2 Book: Darwin, Francis ed. 1887. The life and letters of Charles Darwin, including an autobiographical chapter. vol. 2. London: John Murray. Text Image PDF

paper on the subject. I can hardly doubt that many curious points would occur to any one thoroughly instructed in the subject, who would consider a group of beings under this point of view of descent with modification. All those forms which have come down from an ancient period very slightly modified ought, I think, to be omitted, and those forms alone considered which have undergone considerable change at each successive epoch. My fear is whether brachiopods have changed enough. The absolute

59%

F1452.3 Book: Darwin, Francis ed. 1887. The life and letters of Charles Darwin, including an autobiographical chapter. vol. 3. London: John Murray. Text Image PDF

, i. 328. BRODERIP. Boulders on the Azores, ii. 112, 113. transported by floating ice, paper on, i. 302. Bournemouth, residence at, ii. 383. Bowen, Prof. F., hostile review by, in the 'Memoirs of the American Academy of Sciences,' ii. 349, 354; Asa Gray on the opinions of, ii. 359; on heredity, ii. 372. Brace, Mr. and Mrs. C. L., visit to Down, iii. 165. Brachiopoda, evidence from, of descent with modification, ii. 366. Brain, size of the, in the sexes of ants, iii. 191. Branch-climbers, iii. 317

54%

F2539 Periodical contribution: Darwin, C. R. 1891. [Letter to Duke of Argyll, 1878]. Darwin on the unity of the human race. Nature, (5 March): 415. Text PDF

, however, it be assumed that a species at each successive stage of its modification was surrounded in two distinct countries or times by exactly the same assemblage of plants and animals, and by the same physical conditions, then I can see no theoretical difficulty to such a species giving birth to the new form in the two countries. If you will look to the sixth edition of my 'Origin,' at p. 100, you will find a somewhat analogous discussion perhaps more. Yours faithfully, Charles Darwin

64%

F1461 Book: Darwin, Francis ed. 1892. Charles Darwin: his life told in an autobiographical chapter, and in a selected series of his published letters [abridged edition]. London: John Murray. Text Image PDF

Your boldness, however, sometimes makes me tremble, but as Huxley remarked, some one must be bold enough to make a beginning in drawing up tables of descent. Although you fully admit the imperfection of the geological record, yet Huxley agreed with me in thinking that you are sometimes rather rash in venturing to say at what periods the several groups first appeared. I have this advantage over you, that I remember how wonderfully different any statement on this subject made 20 years ago, would

60%

F1461 Book: Darwin, Francis ed. 1892. Charles Darwin: his life told in an autobiographical chapter, and in a selected series of his published letters [abridged edition]. London: John Murray. Text Image PDF

A letter from Lyell to Hooker (Mar. 9, 1863), published in Lyell's Life and Letters, vol. ii. p. 361, shows what was his feeling at the time: He [Darwin] seems much disappointed that I do not go farther with him, or do not speak out more. I can only say that I have spoken out to the full extent of my present convictions, and even beyond my state of feeling as to man's unbroken descent from the brutes, and I find I am half converting not a few who were in arms against Darwin, and are even now

59%

F1592.1 Book: Marchant, James ed. 1916. Alfred Russel Wallace letters and reminiscences. London: Cassell. Volume 1. Text Image PDF

prevision of the enormous and all-important influence which that doctrine was destined to exercise upon every line of human thought. . . . It is in its application to the problems of human society that there still remains an enormous field of work and discovery for the Darwin- Wallace doctrine. In the special branch of study which Wallace himself set going the inquiry into the local variations, races, and species of insects as evidence of descent with modification, [page] 12

57%

F1592.2 Book: Marchant, James ed. 1916. Alfred Russel Wallace letters and reminiscences. London: Cassell. Volume 2. Text Image PDF

really do not go so far as he did. For he maintained that there was not any proof that the several great classes or kingdoms were descended from common ancestors. I maintain, on the contrary, that all without exception are now proved to have originated by descent with modification but that there is no proof, and no necessity, that the very same causes which have been sufficient to produce all the species of a genus or Older were those which initiated and developed the greater differences. At

57%

F1592.2 Book: Marchant, James ed. 1916. Alfred Russel Wallace letters and reminiscences. London: Cassell. Volume 2. Text Image PDF

certainly does, but the writer was highly imaginative, and, like all the other anticipators of Darwin, did not perceive the whole scope of his idea, being, as he himself says, not sufficiently acquainted with the facts of nature. His anticipations, however, of diverging lines of descent from a common ancestor, and of the transmission of disease germs by means of insects, are perfectly clear and very striking. As you yourself made known one of the anticipators of Darwin, whom he himself had

49%

F1592.2 Book: Marchant, James ed. 1916. Alfred Russel Wallace letters and reminiscences. London: Cassell. Volume 2. Text Image PDF

Forest superintendency, 302, 303; on Island Life, 305, 306; on Darwin's criticism of Island Life, 308; on Darwin's Movements of Plants, 311; on land migration of plants, 311; on Civil List pension, 314, 315; on Progress and Poverty, 317; on Darwin's Earthworms, 320 Wallace, Alfred Russel, letters to Sir Francis Darwin: on Darwin's Life and Letters, ii. 39; on descent with modification, 78; on mutation, 80 letter to Mr. W. J. Farmer, on final cause of varying colour of hairs, etc., ii. 101 2