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Now it has been sometimes objected that to deny the inheritance of acquired characters is equivalent to denying the possibility of all modification in descent, since every new modification must be "acquired " by the species at some period of its existence. This objection is, of course, based upon an initial misconception of the recognised meaning of the word "acquired" in this connection.

By an "acquired" character is meant a character which is not in any sense present in the fertilised ovum from which the organism it belongs to was developed, but is acquired by that organism at some period after the first cell-division.

An inherent or congenital character, on the other hand, is a character which does exist potentially in the fertilised ovum before the first cell-division.

The question before us can then be expressed concisely as follows: "Can an acquired character become congenital?"

It is well-known that Erasmus Darwin* and, later, Lamarck † conceived the idea that species are not immutable, and that the individuals representing them at the present day are descended from other simpler forms; that Lamarck explained this process of evolution chiefly by an innate tendency to development along certain lines, partly by the growth of organs in response to a desire on the part of the animal, and partly by the transmission of the effects of increased use and disuse, of habit, or of the direct effects of the environment. It is clear that the last class of means of transmutation indicated is the only attempt at a scientific explanation of the phenomena in question; of the other explanations, the first is essentially unscientific, and the second is too preposterous to need discussion. The last suggestion is, however, in quite a different position. We know that as a matter of fact increased use or disuse of a particular part has, during a single lifetime, a considerable effect on that part; and we are familiar with changes produced in an individual by the direct effect of the environment. What more natural than to suppose that such considerable changes are hereditary, and that in course of time their accumulation will effect a modification of specific rank? So thought Lamarck, and he accordingly formulated his "second law:" "Everything that nature has made individuals acquire or lose by the influence of circumstances under which their race is placed for a long time, and consequently by the influence of the predominant use of a particular organ, or by that of a continual falling off in the use of such a part, she preserves by the act of generation to the new individuals which follow, provided that the acquired modifications are common to the two sexes, or to those individuals which have produced the new one." It is obvious that this "law" is

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quite inadequate to account for all the phenomena of organic evolution. It offers, for example, no explanation of all the complex and wonderful phenomena of adaptation. As we have seen, it only furnished a small part of Lamarck's explanation. His philosophy completely failed to convince the great mass of thinking men of the truth of evolution. Goethe was perhaps the most notable and enthusiastic of his few partisans; but later on, as Mr. Herbert Spencer tells us,* there was a small band of evolutionists in England who accepted Lamarck's second law as at least a partial explanation of that transmutation of species which they believe had taken place. For the rest they were totally at a loss. Hardly a biologist or geologist agreed with them. Sir Charles Lyell had argued brilliantly against Lamarck: Mr. Huxley was a firm anti-evolutionist. Then came the "Origin of Species," with the luminous principle of natural selection, which has effected so profound a change in the attitude of the world to the doctrine of evolution, and which is too familiar to need exposition here. We may, however, point out the great and fundamental difference between the Lamarckian and Darwinian theories of evolution. Apart from the fact that that part of Lamarck's explanation which is alone worthy of serious consideration constitutes but a small portion of his whole conception, we must remember that even this is a mere à priori speculation, and is not supported by a single fact of observation or experiment. Darwin's theory of natural selection, on the other hand, rests secure on the threefold base of the facts of variation, of heredity, and of the struggle for existence. And the method by which these "factors" must co-operate to secure the "survival of the fittest " is obvious as soon as it is stated. In other words natural selection is a vera causa, and its enemies are obliged to confine themselves to the task of trying to demonstrate that at most it can effect but little in the direction of the transmutation of species.† And in addition to this the results of artificial selection by breeders can be pointed to for the demonstration of what actually has been done by a selective process continued for many generations. But we cannot adduce similar considerations on behalf of the so-called Lamarckian factor. It has never been proved to be a vera causa, and for this reason-while the facts of the modification of organs by use and disuse, or by the direct action of the environment during an individual lifetime are perfectly well established, the inheritance of the effects of such modifications are

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tion-which has until just recently been accepted unhesitatingly-bring forward a mass of indirect evidence in support of their view; nevertheless, it is quite apparent that so long as direct experimental evidence, about which no doubt can exist, is wanting, this fundamental insecurity must exist. But to this subject we shall return later.

It is hardly necessary to remind any one familiar with Mr. Darwin's works that he considered certain phenomena to be only explicable as the inherited effects of increased use or disuse of particular organs. Many of the phenomena of degeneration, for instance, in a useless organ, he thought were due to the effects of disuse. He expressly states * that the working of this factor is always subordinate to natural selection, and that in some cases its effects are destroyed by the latter; but there is no doubt, as Mr. Herbert Spencer has shown, † that, as time went on, he attributed increasing importance to this factor; that he was, in fact, driven slightly from his original position by hostile criticism. Later in life, too, he became convinced that the cumulative direct effect of changed conditions had been important in some cases, especially where partial or complete isolation allowed them to have full effect. In a letter to Professor Wagner in 1876, ‡ he goes so far as to “In my opinion the greatest error which I have committed has been not allowing sufficient weight to the direct action of the environment, i.e. food, climate, etc., independently of natural selection."

say,

But although Mr. Darwin believed in the transmission by heredity of "acquired modifications," I think it is a mistake to suppose that he derived his belief from Lamarck's teaching. No one doubted, until quite recently, that characters acquired during the life of the individual were hereditary equally with congenital ones. Mr. Darwin found that he could not explain certain phenomena by natural selection, and thought that they were best explicable as the result of increased use or disuse, etc. The explanation formed but a small part of Mr. Darwin's theory, as it had of Lamarck's, but while it was scientifically the strongest portion of the Lamarckian doctrine of evolution, it was the weakest of the Darwinian. We know that Mr. Darwin did not estimate the "Philo. sophie Zoologique " very highly. Thus he says: "It is curious how largely my grandfather, Dr. Erasmus Darwin, anticipated the views and erroneous grounds of opinion of Lamarck in his 'Zoonomia' (vol. i. pp. 500-510), published in 1794."§ Again, he remonstrates with Lyell in 1863 for alluding to his (Darwin's) views as "a modification of Lamarck's doctrine of development and progression," and remarks that "this way of putting the case is very injurious to its acceptance, as it implies necessary progression, and

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closely connects Wallace's and my views with what I consider, after two deliberate readings, as a wretched book, and one from which (I well remember my surprise) I gained nothing." In a letter to Hooker he characterises the "Philosophie" as "veritable rubbish,” † and finally in [October, 1859, just before the publication of the "Origin" we find the following remark as the postscript of a letter to Lyell: "You often allude to Lamarck's work; I do not know what you think about it, but it appeared to me extremely poor; I got not a fact or idea from it." With these very definite and strong statements of Darwin before us we can hardly contend, I think, that he borrowed his views about the inheritance of acquired characters from Lamarck. In his "Historical Sketch," prefixed to the sixth edition of the "Origin," he calls attention to the "eminent service" done by Lamarck in "arousing attention to the probability of all change in the organic world being the result of law;" (p. xiv.) but there is no word of praise for that part of the French naturalist's theory of evolution which coincides with some of Darwin's own views. I do not think there remains a doubt that the "trace of Lamarckism" often alluded to as remaining in the Darwinian theory, is not Lamarckism at all, except in the sense that Lamarck advocated similar views. As I have said, at the time when the "Origin" was thought out and written, and for a long while afterwards it had never occurred to any one to doubt that acquired characters could be inherited, and it was natural enough for Darwin to use this universally accepted factor to supplement natural selection. We find his nearest approach to dogmatism on this subject: "Changed habits produce an inherited effect, as in the period of the flowering of plants when transported from one climate to another, etc." § The naturalness of such an occurrence being obviously taken for granted, there is in many cases hardly an attempt at proof, and very seldom is the evidence for and against the explanation given worked out and weighed with the minute and painstaking care to which we are accustomed in all Darwin's works.

I have insisted on these considerations because it seems of very considerable importance to ascertain Darwin's exact attitude towards the views in question, how and why he acquired them, and what relation they bore in his mind to the theory of natural selection. And it seems nearly certain that, unlike that great hypothesis, the inheritance of acquired characters was used as an obvious supplemental explanation, and that a doubt of the truth of its fundamental facts never entered Darwin's head. But I deny that Darwin "partially retained the Lamarckian explanation," thereby deliberately adopting any of the speculative "laws" of the

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French naturalist. Mr. Platt Ball, in his little book on the "Effects of Use and Disuse," holds this view, and even remarks that "Darwin's belief in the inheritance of acquired characters was more or less hereditary in the family," instancing his father's and grandfather's views on this point. Unless Mr. Ball is prepared to maintain that there was a special inherent predisposition in the Darwin family towards this belief, he is here assuming the inheritance of an acquired character!

As has been already mentioned, Mr. Darwin attributed more and more importance to this factor in the successive editions of the "Origin," and his opinion on the point culminated in the letter to Professor Wagner already quoted.* It is remarkable too, that he was constrained to form a theory of heredity on the lines of Pangenesis largely to explain these very phenomena. In a letter to Huxley, speaking of his as yet unpublished hypothesis of Pangenesis, he says: "I think some such view will have to be adopted, when I call to mind the inherited effects of use and disuse, etc."+ Here Darwin was absolutely right. As we shall point out more fully hereafter when discussing possible theories of heredity, "some such view" must be adopted if we believe that the effects of use and disuse are inherited. The naturalists who refused to accept the main idea of "Pangenesis" were trying to maintain an untenable position while they believed in such inheritance. Neither Darwin nor they, however, perceived the only possible alternative—an alternative which has now been accepted by many--to re-examine the whole grounds of our belief, and boldly declare that definite proof of such inheritance is wanting. This at once casts the onus probandi upon our opponents, and exempts us from the astounding exercise of faith required to believe in the mechanism of Pangenesis.

The history of the growth of opinion since 1859 on the subject of the factors of organic evolution is too long a story to be more than touched upon here. But the extreme views which have sprung up on both sides, and the complete chain of connection between them are sufficiently remarkable. On the one hand we have the Neo-Lamarckians; in the main an American school of paleontologists, (of whom Professor Cope is perhaps the best-known member) who reduce the action of natural selection to an almost negligeable minimum, and consider that use and disuse, etc., have been the main agents in the evolution of such structures, for instance, as the mammalian tooth. Professor Eimer in Germany and Mr. Cunningham in England hold somewhat similar views. Then we have a class of biologists like Mr. Patrick Geddes, who believes in natural

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selection to a certain extent, but rather uses it to supplement various more or less ingenious theories of his own, which appear to him to account for the main facts of evolution better than do Darwin's.

Next we have Mr. Herbert Spencer (and his followers) who stands in a distinctly different position to any of the foregoing, inasmuch as he believed in evolution before 1859, and therefore certainly does not owe from a speculative point of view so much to Darwin's work as do most other people. Mr. Spencer believes, and always did believe, that all organisms are being directly and profoundly affected from moment to moment by the environment, and that the modifications so brought about cannot fail to be transmitted to their offspring. He believes too, that modifications of function in the individual life effect permanent modifications of function and structure in phylogeny (or life of the species) independently of natural selection. This continual direct attempt, as it were, on the part of an organism to adjust itself to its environment he calls "Direct Equilibration." He accepts the process of natural selection, also, as an important factor, and calls it "Indirect Equilibration," i.e., the indirect process of adjustment to environment, through variation, and the survival of the fittest.

These are the views enunciated in the "Principles of Biology," and quite lately in two articles in the "Nineteenth Century" for 1886* he has emphasised them, and added new arguments and fuller evidence.

Professor Burdon-Sanderson has suggested that those who think such factors as the ones specially worked out by Mr. Spencer to be true factors and of extensive application should be called "Spencerians" rather than Lamarckians, because, as has already been pointed out, such views as these formed but an insignificant portion of the Lamarckian doctrine of evolution, while they have always been insisted on as most important by Mr. Spencer, who has, in addition, expressed them in a more general form and widened their meaning and application. The appellation would certainly serve to distinguish the people in question on the one hand from the extreme Neo-Lamarckians, and on the other from true Darwinians.

Next to the Spencerians we have biologists with views like Professor Romanes, who claim to be the true Darwinians, in holding the position of Darwin's later years. They consider natural selection to be the main factor, but recognise various others as supplementary to it, such as "physiological selection," and the effects of other kinds of segregation, either physiological or geographical, and in some cases recognising to a greater or less extent the Spencerian or Lamarckian factors, or else reserving their judgment on this point. Closely following on these, we have, so far as my experience has gone,

* Reprinted as "The Factors of Organic Evolution."

the main body of working biologists, who do not, perhaps, go so far as the Neo-Darwinians, but whose continually enlarging experience of the wonderful and beautiful adaptations to be found in every nook and cranny of the organic world and constantly coming to light in their studies-anatomical, histological, physiological, or bionomic-makes them firm believers in natural selection, as overwhelmingly the most important cause of evolution, and gives them a reluctance-justifiable or the reverse-to place much confidence in such supplementary factors as those I have mentioned.

Lastly we have the extreme "Neo-Darwinians," as Professor Ray Lankester has called them, whose position may be summarised as follows. They

assert:

(1) That the inheritance of any character acquired by an individual during its lifetime has never been experimentally proved: (2) that hence we are not justified in explaining any of the facts of evolution by any process which involves such inheritance: (3) that these facts can be as well or better explained by natural selection and kindred selective processes in conjunction with the effects of training during the individual life-time than by the alleged inheritance of acquired characters, and that hence the indirect evidence for such inheritance can be refuted, and (4) that the onus probandi rests, not on them, but on their opponents, who would retain an unproved and unnecessary (though hitherto universally-accepted) factor, in our explanation of evolution.

Professor Weismann, Professor Lankester, Professor Meldola, Mr. Wallace, and Mr. Poulton are examples of some of the more distinguished of the NeoDarwinians.

In subsequent papers we shall be chiefly occupied in investigating the justification of their views.

THE WHITE FLOWER QUESTION.
By FRED. H. DAVEY.

́T would indeed be passing strange if the interest

to some profitable conclusion. It is one of the branches of botany which has notoriously held the background, notwithstanding the probabilities that it might ultimately throw valuable light on the origin of new varieties, and thus minimise the labours of the large and indefatigable band of biologists who give their whole energies to a solution of the problem. Albinism in the animal kingdom, more particularly in the genus homo, has long been an interesting field of labour to scientists, and from all accounts has led to good results, so far as it has been proved albino varieties may at times possess the power of transmitting their peculiarities to their offspring. I don't mean to assert it is an established fact that albinism in the human family is hereditary. But I do say it is now beyond the range of probabilities that in the

lower animal creation, at least, albino varieties have begotten progeny with similar tendencies. Why, then, seeing it is of such vital importance, has the subject of white variations in the vegetable kingdom been so monstrously neglected?

I for one must object to the word albinism being used in reference to floral variations which assume a whitish colour. By an albino I understand an animal possessing white feathers, white fur, white hair, or a white skin, with the addition of pink or red eyes. I freely admit in either instance the variation may be the result of similar pathological modifications, but even that hardly warrants a use of the same term in both cases. Were it so, we might with as good reason term the sweat-glands of the human body stomata, or the system of tissues through which nourishment is conveyed to the extremities of a plant the alimentary canal.

One cannot be too cautious in advancing opinions on a subject so wide in its range and fraught with so many difficulties; and of course, not being a practical biologist, I dare not dogmatise in this case. But to myself, as I presume has likewise been the case with a great many readers of SCIENCE Gossip, the question naturally suggests itself, "How best to account for these deviations?" Do they occur through a modification of the pigment cells? Is there an intensified oxidation of the chromule? Is there really an absence in the pigment of certain elements essential to the normal colouring? Or are these variations the outcome of a progressive or retrogressive development of colouring-matter? Pertinent questions these, although such as ought to be partly, if not even wholly, met by the more advanced readers of, and contributors to, these columns. Will they come to our rescue? I am daily more and more convinced of the importance of the subject, and am certain many others will with myself feel grateful for any light.

This district is inordinately prolific in the way of white variations. From Bissoe my father has repeatedly brought pure white specimens) of Calluna erica, Erica cinerea, and E. tetralix, and a few beautiful white heads of Centaurea nigra. From the Lizard I have had huge bunches of Erica vagans brought me, embracing every shade from snowy white to deep purple. My father entertains no doubt at all on the plants he has seen producing white flowers year after year. Some of them he has carefully watched for upwards of twenty years without being able to detect the remotest disposition on their part to return to the normal colour. Erica ciliaris, on the contrary, never produces in this locality any but the rich pink flowers.

The most peculiar variation coming under my own notice was a low, dwarf-like variety of Wahlenbergia hederacea, bearing elegant white flowers, if anything a little more bell-shaped than those of the type-form. The plant cropped up in quantities some five years

ago in a small bog close by, and continued to thrive there up to last summer. What struck me as the most remarkable feature of the case, was that the little pigmy grew in a straight line across the moor, at no part spreading more than three or four feet. It was a pretty sight to stand at one end and trace this dainty morsel right across-here just peeping over the trailing pennywort, and there over-topped by the lesser skull-cap-and then to compare it with the more elegant trailing branches and delicate pale-blue flowers of the normal plant which blossomed profusely all round.

In addition to the plants mentioned we have noticed white varieties of Ranunculus ficaria, Aquilegia vulgaris, Viola canina, Polygala vulgaris, Geranium molle, Erodium maritimum, Sedum anglicum, Epilobium montanum, Valeriana officinalis, Fasione montana, Primula vulgaris, Polemonium cæruleum, Symphytum officinale, Myosotis palustris, Digitalis purpurea, Veronica chamadrys, Pedicularis sylvatica, Thymus serpyllum, Prunella vulgaris, Ajuga reptans.

This list is a very significant one, and, if Grant Allen's theory of progressive colour development goes for aught, argues conclusively a movement on retrogressive lines. It will be noticed that in this list, as well as in the one submitted last month by E. Armitage, only two plants with yellow flowers figure as sporting into white. In his progressive colour. scale, Mr. Allen gives yellow, white, red, purple, lilac, mauve, violet, and blue; white being an improvement on the yellow, red on the white, etc. Our two lists show a remarkable preponderance of blue over the yellow, and of red over the blue, driving one to the conclusion that as red is an improvement on white, and blue is the highest stage of development, white variations from the type indicate a retrogressive rather than a progressive development of colouring-matter.

Of course these are merely a few suggestions. I may be right or wrong in assuming the subject to be of vital importance, or in objecting to the word albinism being used in reference to this subject. I may be equally right or wrong on the progressive or retrogressive colour theory, or in my assumptions on the oxidation of chromule, on the absence or presence of certain elements in the pigment, or in the modification of the pigment cells. Be that as it may, these suggestions may help to focus our attention, and thereby enable us to deal practically with the problem.

Pousanooth, Perran-ar-worthal, Cornwall.

SCIENCE-GOSSIP.

WE have received a reprint from " Inventions," giving an account of Mr. James Nelson's ingenious "Calculating Dial," as furnishing a ready means for calculating figures in commercial business.

THE celebrated collection of recent shells formed by the late Sir David Barclay, Bart., was sold by auction at Messrs. Stevens' Rooms, London, on the 6th of July and three following days. The catalogue compiled by Mr. Hugh Fulton contained particulars of 1,200 lots, which included a number of extremely rare species, also many type specimens. The following are some of the highest prices realised for single specimens:-Voluta aulica, £10; Murex Barclayi, £9 10s.; Marginella mirabilis, £6 105.; Strombus taurus, £5 10s.; Conus crocatus, £5 10s. ; Cyclostoma formosa, £4 10s. ; Cypræa bicallosa, £3; Scalaria decussata (two specimens), £4 5s.

A DEEPLY thoughtful, and highly interesting address is that of Dr. A. Leifius, delivered before the Royal Society of New South Wales (London: Kegan Paul & Co.).

DR. J. E. TAYLOR has just published verbatim the "Story of the Felixstowe Crags "(illustrated), as told by him to a public audience at Felixstowe on Wednesday, July 29 (Ipswich: "East Anglian Daily Times" Office, price sixpence).

THE second quarterly number of "The Conchologist" (edited by W. E. Collings) is even better than the first. It cannot fail to prove a welcome guest among all interested in Conchological subjects.

THE Report of the Botanical Exchange Club for 1890 (Manchester, Jas. Collins & Co., King St.) is as valuable an accession to our botanical literature as usual. No English botanist should be without it.

THE third number of the "Mediterranean Naturalist "demonstrates that a welcome and useful periodical has joined our ranks.

DR. C. W. RILEY'S "Report of the Entomologist for 1890," is even more readable and suggestive than is usual with this distinguished entomologist's "Reports."

THE "Garner" is now amalgamated with the "Naturalist's Gazette," and both in the new form are published at one penny monthly.

WE have received a most interesting and thoughtful brochure, by F. Howard Collins, on "The Diminution of the Jaw in Civilised Races, an Effect of Disuse." Of course, the author refers to eatingnot to politics or "social" subjects.

SIR GEO. B. AIRY, late Astronomer Royal, is the doyen of British science. He has just entered his ninety-first year, and appears to be as bright and chippy as ever.

AFTER re-consideration the President of the Board of Trade has granted a licence to the British Institute of Preventive Medicine to register the institution as a limited liability company with the omission of the word "limited." The licence, however, is not to be

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