was not a practical naturalist. The case of Lamarck was very different. A close observation of Nature brought him to the same position in which Darwin afterwards found himself. The insight, from what we are accustomed to regard as a purely modern point of view, of observations recorded a century ago is almost startling. Two passages must suffice:

'In the same climate a great difference of situation and exposure causes individuals to vary; but if these individuals continue to live, and to be reproduced under the same difference of circumstances, distinctions are brought about in them which become in some degree essential to their existence.'

'Is not the cultivated wheat a vegetable brought by man into the state in which we now see it? Let anyone tell me in what country a similar plant grows wild, unless where it has escaped from the cultivated fields. Where do we find in Nature our cabbages, lettuces, and other culinary vegetables in the state in which they appear in our gardens?

Such statements, and much else that Lamarck states with absolute accuracy, were destructive of the old dogma of the constancy of species; but they fell for the most part on deaf ears a fact which can only be accounted for by the deafness being correlated with blindness to observation. At any rate, the fundamental fact of variation was established. The old definitions of species given by Ray and Linnæus were disposed of. Lamarck substituted for them the following:

'A species consists of a collection of individuals resembling each other, and reproducing their like by generation, so long as the surrounding conditions do not alter to such an extent as to cause their habits, character, and forms to vary.'*

The most orthodox Darwinian can find nothing in this to which he could take exception. Variation is an empirical fact accepted both by Lamarck and Darwin. To the former, however, it was a direct and adaptive response to the action of the environment; to the latter it was arbitrary and indifferent, and adjustment to changed conditions was accomplished by the selective preservation of such modifications as were suited to them.

Lamarckism deserves some respectful attention, apart from its historical interest. It underlies the remarkable attempt to construct a system of philosophy on evolutionary lines which we owe to Mr. Herbert Spencer. It has for

*This and preceding quotations are borrowed from Lyell, 'Principles of Geology,' vol. ii. pp. 247-250.

that reason, possibly, influenced in a remarkable degree the whole trend of biological research in the United States; and it may be suspected that a rigid investigation would find its influence lurking in many of the projects for social amelioration in our own country.

The most important factor in the production of new forms, according to Lamarck, was the inheritance of acquired characters.' This was expressed in his fourth

law :

'All which has been acquired or laid down or changed in the organisation of individuals in the course of their life, is conserved by generation and transmitted to the new individuals which proceed from those which have undergone these changes.'

But the attempt to sustain this hypothesis either by observation or experimental evidence has entirely failed. Such cases as the occurrence of blind animals in caves, which seemed at first sight to be explicable on Lamarck's theory, prove to be better explained by the Darwinian principle; and if the à priori arguments will not stand the test of examination, the results of direct experiment supply no confirmation. As Lankester has observed:

'No case of the transmission of the results of an injury can be produced. Stories of tailless kittens, puppies, and calves born from parents one of whom had been thus injured are abundant, but they have hitherto entirely failed to stand before examination.' (L.c., p. 375.)

In such a case one may almost say the wish is father to the thought. There is no more pathetic feature in human experience than to see descend into the grave, to pass away for ever, all those endowments with which genius and labour have adorned individual human beings. The cunning hand of the artist, the entrancing skill of the musician, the song of the poet, the eloquence of the orator-all perish with their possessors and leave not a wrack behind.' Were it otherwise, the toil of education would have been mitigated, and there would have been no bounds to the mental acquirements of the race. But when our first parents tasted of the tree of knowledge, the tree of life was denied them, and knowledge perishes with its possessor.

The brief historical sketch which has been given might have been much extended; but it will suffice to show that as soon as men began to study living organisms they recognised the existence of some principle in their ordering. This is equally true in the field of zoology as in that of

botany. As Lankester has observed, what 'collectors and 'anatomists, morphologists, philosophers, and embryologists had been so long striving after' was the natural classification based on the Theory of Descent.*

The labours of systematists have often provoked impatience and sometimes ridicule, and this more especially perhaps in the case of botanists. Yet it was a careful study of the peculiarities of the flora of the Galapagos Archipelago which Darwin regarded as especially . . . the origin of all my views.' † It would be difficult to give a more striking illustration of the impossibility à priori of deciding on the utility or even intellectual importance of any subject of scientific inquiry.

The Origin' was published in October, 1859. Haughton, a clever Irish mathematician, had already declared that the principle of natural selection was not new. This turned out to be so far true that it had suggested itself to Wells in 1813 and to Matthew in 1831, as indeed it had also done to others. But it is one thing to throw out a suggestion, and another to devote the best part of a life to working out a theory in all its bearings. Writing to Huxley in November, 1859, Darwin said :

'When I put pen to paper for this volume I had awful misgivings, and thought perhaps I had deluded myself, like so many have done; and I then fixed in my mind three judges on whose decision I determined mentally to abide. The judges were Lyell, Hooker, and yourself.' (Life, vol. ii. pp. 232, 233.)

In truth, they were more than judges; they were each and all either accessories before or after the fact. They can never be dissociated from the history of the theory, and were a monument ever to be consecrated to it their effigies would be its appropriate tripodal basis. Hooker had long been in Darwin's confidence, and the rational theory of the geographical distribution of plants which we owe to him was indispensable to Darwin's theory.

'The mutual relations,' he observes, of the plants of each great botanical province, and, in fact, of the world generally, is just such as would have resulted if variation had gone on operating throughout indefinite periods, in the same manner as we see it act in a limited number of centuries, so as gradually to give rise in the course of time to the most widely divergent forms.' (Lyell, 'Principles,' vol. ii. p. 283.) The part which Lyell played is of peculiar interest, both + Life, vol. i. p. 276.

* L.c., p. 342.

in its historical aspect and as an illustration of the working of a scientific temperament of the finest kind. But in truth the Darwinian theory was precisely what was required to give completeness to Lyell's own task. This is admirably expressed by Huxley :—

'I have recently read afresh the first edition of the "Principles of Geology"; and when I consider that this remarkable book had been nearly thirty years in everybody's hands, and that it brings home to any reader of ordinary intelligence a great principle and a great factthe principle that the past must be explained by the present, unless good cause be shown to the contrary; and the fact that, so far as our knowledge of the past history of life on our globe goes, no such cause can be shown-I cannot but believe that Lyell, for others, as for myself, was the chief agent in smoothing the road for Darwin. For consistent uniformitarianism postulates Evolution as much in the organic as in the inorganic world. The origin of a new species by other than ordinary agencies would be a vastly greater "catastrophe than any of those which Lyell successfully eliminated from sober geological speculation.' (Darwin's 'Life and Letters,' vol. ii. p. 190.)

Lyell himself summed up his own earlier position :—

'In former editions of this work [the "Principles"], from 1832 to 1853, I did not venture to differ from the opinion of Linnæus, that each species had remained from its origin such as we now see it, being variable, but only within certain fixed limits. The mystery in which the origin of each species was involved seemed to me no greater than that in which the beginning of all vital phenomena in the earth is shrouded. . . . I pointed out how the struggle for existence among species, and the increase and spread of some of them, must tend to the extermination of others; and as these would disappear gradually and singly from the scene, I suggested that probably the coming-in of new species would in like manner be successive, and that there was no geological sanction for the favourite doctrine of some theorists, that large assemblages of new forms had been ushered in at once to compensate for the sudden removal of many others from the scene.' (Principles, vol. ii. pp. 267, 268.)

Lyell was therefore on the same track as Darwin, and, but for the old stumbling-block of the constancy of 'species,' might have arrived at the same goal. Like Darwin, he rejected the views of Lamarck because they rested upon an assumption of a law of innate progressive 'developement which could not be shown to be in ' accordance with natural facts.' But he was, though not without some hesitation, ultimately converted to the views of the former. As Wallace remarked:

The history of science hardly presents so striking an instance of youthfulness of mind in advanced life as is

'shown by the abandonment of opinions so long held and so 'powerfully advocated.'*

The developement of Huxley's views is scarcely less instructive. He tells us :

'I remember, in the course of my first interview with Mr. Darwin, expressing my belief in the sharpness of the lines of demarcation between natural groups and in the absence of transitional forms, with all the confidence of youth and imperfect knowledge. I was not aware at that time that he had been many years brooding over the species question, and the humorous smile which accompanied his gentle answer, that such was not altogether his view, long haunted and puzzled me.' (Huxley's Life and Letters,' vol. i. p. 169.)

How Huxley gradually emancipated himself may be told in his own words :

'I think I must have read the "Vestiges" before I left England in 1846, but, if I did, the book made very little impression upon me, and I was not brought into serious contact with the " Species" question until after 1850. At that time I had long done with the Pentateuchal cosmogony, which had been impressed upon my childish understanding as Divine truth, with all the authority of parents and instructors, and from which it had cost me many a struggle to get free. But my mind was unbiassed in respect of any doctrine which presented itself, if it professed to be based on purely philosophical and scientific reasoning. It seemed to me then (as it does now) that "creation," in the ordinary sense of the word, is perfectly conceivable. I find no difficulty in conceiving that, at some former period, this universe was not in existence, and that it made its appearance in six days (or instantaneously, if that is preferred) in consequence of the volition of some pre-existing Being. Then, as now, the so-called à priori arguments against Theism-and, given a Deity, against the possibility of creative acts-appeared to me to be devoid of reasonable foundation. I had not then, and I have not now, the smallest à priori objection to raise to the account of the creation of animals and plants given in "Paradise Lost," in which Milton so vividly embodies the natural sense of Genesis. Far be it from me to say that it is untrue because it is impossible. I confine myself to what must be regarded as a modest and reasonable request for some particle of evidence that the existing species of animals and plants did originate in that way, as a condition of my belief in a statement which appears to me to be highly improbable.

And, by way of being perfectly fair, I had exactly the same answer to give to the evolutionists of 1851-58. Within the ranks of the biologists at that time I met with nobody, except Dr. Grant, of University College, who had a word to say for Evolution— and his advocacy was not calculated to advance the cause. Outside these ranks, the only person known to me whose knowledge and

* Darwin, 'Life,' iii. pp. 114, 115.