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full résumé of the positions they took in regard to it. I will also touch briefly upon some other writers who have handled the same subject. The reader will thus be enabled to follow the development of a great conception as it has grown up in the minds of successive men of genius, and by thus growing with it, as it were, through its embryonic stages, he will make himself more thoroughly master of it in all its bearings.

      I will then contrast the older with the newer Darwinism, and will show why the 'Origin of Species,' though an episode of incalculable value, cannot, any more than the 'Vestiges of Creation,' take permanent rank in the literature of evolution.

      It will appear that the evolution of evolution has gone through the following principal stages:—

      I. A general conception of the fact that specific types were not always immutable.

      This was common to many writers, both ancient and modern; it has been occasionally asserted from the times of Anaximander and Lucretius to those of Bacon and Sir Walter Raleigh.

      II. A definite conception that animal and vegetable forms were so extensively mutable that few (and, if so, perhaps but one) could claim to be of an original stock; the direct effect of changed conditions being assigned as the cause of modification, and the important consequences of the struggle for existence being in many respects fully recognized. The fact of design or purpose in connection with organism, as causing habits and thus as underlying all variation, was also indicated with some clearness, but was not thoroughly understood.

      This phase must be identified with the name of Buffon, who, as I will show reason for believing, would have carried his theory much further if he had not felt that he had gone as far in the right direction as was then desirable. Buffon put forward his opinions, with great reserve and yet with hardly less frankness, in volume after volume from 1749 to 1788, the year of his death, but they do not appear to have taken root at once in France. They took root in England, and were thence transplanted back to France.

      III. A development in England of the Buffonian system, marked by glimpses of the unity between offspring and parents, and broad suggestions to the effect that the former must be considered as capable of remembering, under certain circumstances, what had happened to it, and what it did, when it was part of the personality of those from whom it had descended.

      A definite belief, openly expressed, that not only are many species mutable, but that all living forms, whether animal or vegetable, are descended from a single, or at any rate from not many, original low forms of life, and this as the direct consequence of the actions and requirements of the living forms themselves, and as the indirect consequence of changed conditions. A definite cause is thus supposed to underlie variations, and the resulting adaptations become purposive; but this was not said, nor, I am afraid, seen.

      This is the original Darwinism of Dr. Erasmus Darwin. It was put forward in his 'Zoonomia,' in 1794, and was adopted almost in its entirety by Lamarck, who, when he had caught the leading idea (probably through a French translation of the 'Loves of the Plants,' which appeared in 1800), began to expound it in 1801; in 1802, 1803, 1806, and 1809, he developed it with greater fulness of detail than Dr. Darwin had done, but perhaps with a somewhat less nice sense of some important points. Till his death, in 1831, Lamarck, as far as age and blindness would permit, continued to devote himself to the exposition of the theory of descent with modification.

      IV. A more distinct perception of the unity of parents and offspring, with a bolder reference of the facts of heredity (whether of structure or instinct), to memory pure and simple; a clearer perception of the consequences that follow from the survival of the fittest, and a just view of the relation in which those consequences stand to "the circumstance-suiting" power of animals and plants; a reference of the variations whose accumulation results in species, to the volition of the animal or plant which varies, and perhaps a dawning perception that all adaptations of structure to need must therefore be considered as "purposive."

      I also pass over Isidore Geoffroy St. Hilaire's 'Natural History,' which appeared 1854–62, and the position of which is best described by calling it intermediate between the one which Buffon thought fit to pretend to take, and that actually taken by Lamarck. The same may be said also of Étienne Geoffroy. I will, however, just touch upon these writers later on.

      A short notice, again, will suffice for the opinions of Goethe, Treviranus, and Oken, none of whom can I discover as having originated any important new idea; but knowing no German, I have taken this opinion from the résumé of each of these writers, given by Professor Haeckel in his 'History of Creation.'

      V. A time of retrogression, during which we find but little apparent appreciation of the unity between parents and offspring; no reference to memory in connection with heredity, whether of instinct or structure; an exaggerated view of the consequences which may be deduced from the fact that the fittest commonly survive in the struggle for existence; the denial of any known principle as underlying variations; comparatively little appreciation of the circumstance-suiting power of plants and animals, and a rejection of purposiveness. By far the most important exponent of this phase of opinion concerning evolution is Mr. Charles Darwin, to whom, however, we are more deeply indebted than to any other living writer for the general acceptance of evolution in one shape or another. The 'Origin of Species' appeared in 1859, the same year, that is to say, as the second volume of Isidore Geoffroy's 'Histoire Naturelle Générale.'

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