Search Results - The Complete Work of Charles Darwin Online

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A604 Review: Lewes, George Henry. 1868. Mr. Darwin's hypotheses. Fortnightly Review n.s. 3 (April, June); 353-73, 611-28, 4 (July), (November): 61-80, 492-509. Text Image

Selection we have acted solely on the exterior, without in any respect altering the internal and essential parts ( sans en changer en rien la constitution essentielle et profonde ),1 the assertion is in one sense true, in another false; and the sense in which it is true does not oppose the Evolution hypothesis, whereas the sense in which it is false is an argument that upsets the hypothesis of fixed species. Thus it is true that the modification, which can be impressed on an individual, or on a

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A604 Review: Lewes, George Henry. 1868. Mr. Darwin's hypotheses. Fortnightly Review n.s. 3 (April, June); 353-73, 611-28, 4 (July), (November): 61-80, 492-509. Text Image

forth, we admit the fact that specific forms are persistent, but deny that this fact has the slightest value as evidence against the evolution of new specific forms through modification; and affirm that embryology furnishes the plainest testimony that such evolutions do take place. Species, except as a subjective classification of resemblance has no existence. Only individuals with variable resemblance exist; and as these individuals propagate, the propagation is necessarily a reproduction of

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A604 Review: Lewes, George Henry. 1868. Mr. Darwin's hypotheses. Fortnightly Review n.s. 3 (April, June); 353-73, 611-28, 4 (July), (November): 61-80, 492-509. Text Image

the repugnance to using such language of evasion may cause men to revise their conceptions altogether; they dare not attribute ignorance and incompetence to the Creator. Obviously the architectural hypothesis is incompetent to explain the phenomena of organic development. Evolution is the universal process; not creation of a direct kind. Von Baer, who very properly corrected the exaggerations which had been put forth respecting the identity of the embryonic forms with adult forms lower in the

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A604 Review: Lewes, George Henry. 1868. Mr. Darwin's hypotheses. Fortnightly Review n.s. 3 (April, June); 353-73, 611-28, 4 (July), (November): 61-80, 492-509. Text Image

developed from the simpler forms, we ought to trace the identities through all their stages. If the fish developed into the reptile, the reptile into the bird, and the bird into the mammal (which I, for one, think very questionable), we ought to find, it is urged, evidence of this passage. And at one time it was asserted that the evidence existed; but this has been disproved, and on the disproof the opponents of Evolution take their stand. Although I cannot feel much confidence in the idea of

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A604 Review: Lewes, George Henry. 1868. Mr. Darwin's hypotheses. Fortnightly Review n.s. 3 (April, June); 353-73, 611-28, 4 (July), (November): 61-80, 492-509. Text Image

to understand this Idea? If it mean an independent Entity, an agency external to the organism, we refuse to acknowledge its existence. If it mean only an posteriori abstraction, expressing the totality of the momenta, then indeed we acknowledge that it determines the animal form; but this is only an abbreviated way of expressing the law of Evolution, by which each stage determines its successor. The Type does not dominate the momenta, it emerges from them; the animal organism (1) MILNE EDWARDS

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A604 Review: Lewes, George Henry. 1868. Mr. Darwin's hypotheses. Fortnightly Review n.s. 3 (April, June); 353-73, 611-28, 4 (July), (November): 61-80, 492-509. Text Image

for a principle, which has played so conspicuous a part in the history of philosophy. Like many others of its class it exhibits an interesting evolution from the crude metaphysical to the subtle metaphysical point of view, which at last insensibly blends into the positive point of view. At first the Type or Idea was regarded as an objective reality, external to the organism it was supposed to rule. Then this notion was replaced by an approach to the more rational interpretation, the Idea was made

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A604 Review: Lewes, George Henry. 1868. Mr. Darwin's hypotheses. Fortnightly Review n.s. 3 (April, June); 353-73, 611-28, 4 (July), (November): 61-80, 492-509. Text Image

from the immanent properties of the organic molecules, in the fact that it is not reformed at once, but by gradual evolution; the mass of cells at the stump are cells of embryonic character, cells such as those which originally crystalised into muscles, nerves, vessels, and integument, and each cell passes through all its ordinary stages of development. It is to be remembered that so intimately dependent is the resultant on the determining momenta that any external influence which disturbs the

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A604 Review: Lewes, George Henry. 1868. Mr. Darwin's hypotheses. Fortnightly Review n.s. 3 (April, June); 353-73, 611-28, 4 (July), (November): 61-80, 492-509. Text Image

been destroyed; and this is all the more remarkable from the great tenacity of life which the mutilated segments manifest. Quatrefages had observed portions of a worm, after gangrene had destroyed its head and several segments, move about in the water and avoid the light!1 A final argument to show that the reproduction is not determined by any ruling Idea, but by the organic conditions and the necessary stages of evolution, is seen in the re-appearance of a tumour or cancer after it has been

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A604 Review: Lewes, George Henry. 1868. Mr. Darwin's hypotheses. Fortnightly Review n.s. 3 (April, June); 353-73, 611-28, 4 (July), (November): 61-80, 492-509. Text Image

animal life appeared, therefore there could have been no special conditions determining the appearance of Life, the hypothesis of Evolution entirely rejects the notion of organic forms having been diversified by diversities in the few physical conditions commonly understood as representing the Medium. Mr. Darwin has the incomparable merit of having en (1) AGASSIZ, Essay on Classification, 1859, p. 15. VOL. IV. N.S. F [page] 6

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A604 Review: Lewes, George Henry. 1868. Mr. Darwin's hypotheses. Fortnightly Review n.s. 3 (April, June); 353-73, 611-28, 4 (July), (November): 61-80, 492-509. Text Image

becoming universal. In these papers I shall endeavour to sketch the course such a reconciliation may take. I may be deluding myself by a natural prepossession in favour of my own conception of the Evolution Hypothesis, which has been the growth of many years' meditation, and which was very indefinite until Mr. Darwin's work came to give it shape, both by what it furnished of direct instruction, and what it suggested indirectly; but I hope to lay before the reader sufficient evidence to justify the

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A604 Review: Lewes, George Henry. 1868. Mr. Darwin's hypotheses. Fortnightly Review n.s. 3 (April, June); 353-73, 611-28, 4 (July), (November): 61-80, 492-509. Text Image

series becomes more diversified. The structure and development of an organism are dependent on the affinities of its constituent molecules, and it is a biological principle of great importance which Mr. Paget insists on, when he shows how the existence of certain materials in the blood may determine the formation of structures in which they may be incorporated. 2 Any initial diversity may thus become the starting point of a considerable variation in subsequent evolution. Thus, supposing that on

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A604 Review: Lewes, George Henry. 1868. Mr. Darwin's hypotheses. Fortnightly Review n.s. 3 (April, June); 353-73, 611-28, 4 (July), (November): 61-80, 492-509. Text Image

although both plants and animals have albumen, fibrine, and caseine, the derivatives of these are unlike. Horny substance, connective tissue, nerve tissue, chitine, biliverdine, creatine, urea, hippuric acid, and a variety of other products of evolution or of waste, never appear in plants; while the hydrocarbons so abundant in plants are, with two or three exceptions, absent from animals. Such facts imply great differences in elementary composition; and this result is further enforced by the fact

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A604 Review: Lewes, George Henry. 1868. Mr. Darwin's hypotheses. Fortnightly Review n.s. 3 (April, June); 353-73, 611-28, 4 (July), (November): 61-80, 492-509. Text Image

receiving more nutriment, are developed. 1 That which distinguishes Mr. Darwin's hypothesis from all its predecessors is the precision with which it fixes what was vague and shifting, by assigning the several conditions that are necessary. In this respect it is analogous to his hypothesis of Natural Selection, which gave a sudden illumination to the old doctrine of Evolution, by substituting a precise and verifiable conception for the vague or metaphysical conceptions which were current

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A604 Review: Lewes, George Henry. 1868. Mr. Darwin's hypotheses. Fortnightly Review n.s. 3 (April, June); 353-73, 611-28, 4 (July), (November): 61-80, 492-509. Text Image

appreciable relation to the Organism are not properly to be included in its Medium. In consequence of this oversight we frequently hear it urged as an objection to the Evolution Hypothesis, that manifold organisms exist under the same external conditions, and that organisms persist unchanged amid a great variety of conditions. The objection is beside the question. In the general sum of external forces there are certain items which are nearly related to particular organisms, and constitute their Medium

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F912.2 Book: Darwin, C. R. 1868. De la variation des animaux et des plantes sous l'action de la domestication. Translated by J. J. Moulinié. Preface by Carl Vogt. Paris: C. Reinwald. vol. 2. Text Image PDF

propageant par bourgeons, rétrogradent si rarement pendant leur développement ; car pour chaque organisme, la conformation acquise à chaque phase de son évolution doit être adaptée à ses habitudes particulières. Or, chez des êtres produits par gemmation, — circonstance qui peut avoir lieu à toute époque de croissance, au contraire de ce qui se passe pour la génération sexuelle, — s'il y avait de la place pour le maintien d'un grand nombre d'individus à un état donné de développement, le mode le

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A606 Review: [Dallas, William Sweetland?]. 1868. [Review of] Variation of animals and plants under domestication. Westminster Review n.s. 35 (January): 207-27. Text Image

show of truth in this statement, it will be found on investigation that the agreement between Lamarck and Darwin is almost limited to their holding in common the opinion that species were not independently created, but produced by evolution from pre-existing organisms. The means by which this result is supposed to have been brought about are quite different in the two theories, and whilst Darwin has the advantage in the precision and rationality of the processes which he endeavours to demonstrate

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A603 Review: [Dawkins, William Boyd]. 1868. [Review of] Variation of animals and plants under domestication. Edinburgh Review 128 (October): 414-50. Text Image

,'* by his careful researches and earnest writings. In all probability the naturalists of the future, while endorsing his principle, will deny to selection the paramount power with which it is invested in his theory of evolution. Mr. Darwin concludes with an attempt to account for the obscure facts presented by reproduction, heredity, and variation, by the following hypothesis, which is very likely to be true, although it is not capable of direct proof: 'It is almost universally admitted that

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A263 Book: Müller, Fritz. 1869. Facts and arguments for Darwin. Translated by W. S. Dallas. London: John Murray. Text Image PDF

CONTENTS. ~~~~~~~~~~~~~~~~ CHAP. PAGE I. INTRODUCTORY. 1 II. THE SPECIES OF MELITA. 7 III. MORPHOLOGY OF CRUSTACEA. 13 IV. SEXUAL PECULIARITIES AND DIMORPHISM. 19 V. RESPIRATION IN LAND CRABS. 30 VI. STRUCTURE OF THE HEART IN EDRIOPHTHALMA. 39 VII. DEVELOPMENTAL HISTORY OF PODOPHTHALMA. 47 VIII. DEVELOPMENTAL HISTORY OF EDRIOPHTHALMA. 69 IX. DEVELOPMENTAL HISTORY OF ENTOMOSTRACA, CIRRIPEDES, AND RHIZOCEPHALA. 83 X. ON THE PRINCIPLES OF CLASSIFICATION. 97 XI. ON THE PROGRESS OF EVOLUTION. 110

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A263 Book: Müller, Fritz. 1869. Facts and arguments for Darwin. Translated by W. S. Dallas. London: John Murray. Text Image PDF

have been inserted in their proper places, and two longer pieces, one forming a foot-note near the close of Chap. XI. (p. 119), the other at the end of Chap. XII. (pp. 135-140), describing the probable mode of evolution of the Rhizocephala from the Cirripedia. Of the execution of the translation I will say but little. My chief object in this, as in other cases, has been to furnish, as nearly as possible, a literal version of the original, regarding mere elegance of expression as of secondary

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A263 Book: Müller, Fritz. 1869. Facts and arguments for Darwin. Translated by W. S. Dallas. London: John Murray. Text Image PDF

CHAPTER XI. ON THE PROGRESS OF EVOLUTION. FROM this scarcely unavoidable but unsatisfactory side-glance upon the old school, which looks down with so great an air of superiority upon Darwin's intellectual dream and the giddy enthusiasm of its friends, I turn to the more congenial task of considering the developmental history of the Crustacea from the point of view of the Darwinian theory. Darwin himself, in the thirteenth chapter of his book, has already discussed the conclusions derived from