ber of individuals presenting these discontinuous variations, we may therefore draw an important conclusion which has hitherto been overlooked. It is, that not only do such variations afford no support to the theory of a special "organic stability" capable of producing races, species, and even genera, without any aid from natural selection, but they furnish a strong, if not conclusive, argument against it, since any which did possess such exceptional stability, and were in no degree injurious, would long since have become equal in numbers to the type of the species.

Laws of Growth, Importance of.

A few words are here necessary as to the very common misconception that extreme Darwinians do not recognise the importance of the organism itself and of its laws of growth and development, in the process of evolution. For myself, I may say that no one can be more profoundly impressed by the vast range, by the complexity, by the mystery, by the marvellous power of the laws and properties of organised matter, which constitute the very foundation of all life, and which alone render possible its countless manifestations in the animal and vegetable worlds; while those who have read Weissmann's account of the complex processes of development of sperm and germ cells, in his volume on The Germ Plasm, must feel sure that he, at all events, can have no inadequate conception of their importance.

What Darwinians deny is-as I understand the question that these laws themselves serve to keep the completed organism in close adaptation to the fluctuating From this law it follows that, as varieties are usually very much less numerous than the species, this must be due to one of the following causes: either (1) the variety has but recently originated, and has not had time to increase; or (2) the variety has ceased to be produced by the species; or (3) it does not reproduce its like sc completely as does the species; or (4) it is disadvantageous to the species. The first two suppositions are improbable, and can only account for a very small proportion of the varieties which are greatly inferior in numbers to the species; the other two are antagonistic to any special ". organic stability," which must, therefore in the great majority of cases be rejected as being both unproven and also opposed to the facts.

environment, instead of merely furnishing the material which is required for that adaptation. In our view, the fundamental laws of growth and development, through the agency of rapid multiplication and constant variability, provide the material on which natural selection acts, and by means of which it is enabled to keep up the adaptation to the environment (which alone renders continuous life and reproduction possible) during the constant, though slow changes, whether inorganic or organic, by which, in the course of ages, the effective environment of each species becomes more or less profoundly modified. Thus, and thus alone, we believe, are new species produced in strict adaptation to the new environment. So far as rendering possible and actually leading to growth, reproduction, and variation, the fundamental laws are supreme. In securing the development of new forms in adaptation to the new environment, natural selection is supreme. Hence arises the real distinction-though we may not always be able to distinguish them-between specific and non-specific or developmental characters. The former are those definite, though slight modifications, through which each new species actually became adapted to its changed environment. They are, therefore, in their very nature, useful. The latter are due to the laws which determine the growth and development of the organism, and therefore they rarely coincide exactly with the limits of a species. The more important of these latter characters are common to much larger groups, as families, orders, or classes, while others, depending partly on complex and fluctuating influences, are variable even within the limits of a species. Of this last kind are the finger-prints, which, like many other minute details of form or structure, vary from individual to individual.

I have now, I think, shown that the two most recent efforts to establish new "methods of organic evolution" as either complete or partial substitutes for natural selection-that is, for the survival of the fittest among the individual variations annually produced-have completely failed to establish themselves as having any relation to the

actual facts of nature. Mr. Bateson's discontinuous variations were long ago rejected by Darwin as having no important part in the formation of new species, while recent and ever-growing proofs of the generality and the magnitude of individual variability, render these larger and rarer kinds of variation of even less importance than in his time. Mr. Galton's theory of organic stability, which is essential to the success of discontinuous variations, has been shown to be founded upon a comparison of things of a totally dissimilar nature, and, further, to be absolutely unintelligible and powerless unless in strict subordination to natural selection.

The reason why two writers of such extensive knowledge and undoubted ability have so completely failed in dealing with the great problem of the modification of organic forms, has been clearly indicated during the course of this discussion. It has arisen from the fact that they have devoted themselves too exclusively to one set of factors, while overlooking others which are both more general and more fundamental. These are, the enormously rapid multiplication of all organisms during more favourable periods, and the consequent weeding out of all but the fittest in what must be on the whole stationary populations. And, acting in combination with this annual destruction of the less fit, is the periodical elimination under recurrent unfavourable conditions, of such a large proportion of each species as to leave only a small fraction-the very elect of the elect to continue the race. It is only by keeping the tremendous severity of this inevitable and never-ceasing process of selection always present to our minds, and applying it in detail to each suggested new factor in the process of evolution, that we shall be able to determine what part such factors can take in the production of new species. It is because they have not done this, that the two authors, whose works have been here examined, have so completely failed to make any real advance towards a more complete solution of the problem of the Origin of Species than has been reached by Darwin and his successors.

CHAPTER XVIII

THE PROBLEM OF UTILITY: ARE SPECIFIC CHARACTERS ALWAYS OR GENERALLY USEFUL?1

THE above stated question is discussed at great length in the second part of the late Mr. Romanes' work on Darwin and After Darwin, fully half of the volume being devoted to it; and in the preface the author states his belief that his arguments are so conclusive that he has "broken to fragments" the doctrine of utility, and that he has "made a full end thereof." A careful perusal of the volume, and a full consideration of all the facts and arguments adduced therein, seem to me to leave the problem just where it was before; but the variety of the subjects discussed, the great mass of details referred to, and the ingenuity of some of the arguments in support of the author's view, lead me to think that I have not hitherto set forth the facts and arguments in favour of the utilitytheory with sufficient completeness, while I am indebted to the lamented author for pointing out one or two weak points in my discussion of the question, and for a number of useful references to Darwin's statements on the points at issue, some of which I had overlooked.

Although Mr. Romanes' discussion of the question is so lengthy, the problem itself is in its essence a comparatively simple one, and is I believe capable of being solved by a reference to well-known facts and admitted principles. The reason why Mr. Romanes is able to support his views

1 This paper was read before the Linnean Society on June 18th, 1896, and printed in the Journal-Zoology, vol. xxv.

by so many quotations from Darwin's works, is due to the fact that Darwin was firmly convinced of the heredity of acquired characters, and especially of the influence of food and climate and the effects of use and disuse; and this belief must be borne in mind whenever he speaks of specific characters being due to other causes than natural selection. It must also be remembered that Darwin was not acquainted with the evidence we now possess as to the extreme frequency of variation everywhere in nature, its large amount, and its universality in every organ and every character that can be measured or otherwise estimated. Had he known what we now know on this subject, he would not so frequently have made the proviso-" if they vary, for without variation natural selection can do nothing," or have alluded to the possibility of variations of the same kind occurring "perhaps after a long interval of time." We now know that variations of almost every conceivable kind occur, in all the more abundant species, in every generation, and that the material for natural selection to work upon is never wanting. Accepting, then, these facts of variation, and always keeping in mind the severity of the struggle for existence, nine-tenths at least of the progeny of the higher animals perishing annually before reaching maturity, thus leading to a systematic and continual weeding out of the less fit-let us endeavour to realise the process of the formation of new species and the nature of the characters which distinguish allied species from each other.

The Principle of Utility.

In my article on " Mimicry and other Protective Resemblances among Animals," first published in 1867, I laid down the principle of utility, perhaps a little too absolutely, in the following passage:-" Perhaps no principle has ever been announced so fertile in results as that which Mr. Darwin so earnestly impresses upon us, and which is indeed a necessary deduction from the theory of Natural Selection, namely that none of the definite facts of organic nature, no special organ, no characteristic form or