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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
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 Eng. land 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
“ 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 Dar. winian 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 d 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.t 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
It is true that the adherents of the theory in ques.
I “Deuxième Loi. Pout ce que la nature a fait acquérir ou perdre aux individus par l'influence des circonstances où leur race se trouve depuis longtemps exposée, et par conséquent
par l'influence de l'emploi prédominant de tel organe, ou par celle d'un défaut constant d'usage de telle partie, elle le conserve par la génération aux nouveaux individus qui en proviennent, pourvu que les changements acquis soient communs aux deux sexes ou à ceux qui ont produit ces nouveaux individus.”—“ Philosophie Zoologique,” tome i. p. 235, édition Savy, 1873. *'*Factors of Organic Evolution,” pp. 2–3.,,
+ E.g., vide Dr. St. G. Mivart, “Nature,” December 6th, 1888.
tion—which has until just recently been accepted closely connects Wallace's and my views with what I unhesitatingly-bring forward a mass of indirect consider, after two deliberate readings, as a wretched evidence in support of their view ; nevertheless, it is book, and one from which (I well remember my quite apparent that so long as direct experimental surprise) I gained nothing." In a letter to Hooker evidence, about which no doubt can exist, is wanting, he characterises the “ Philosophie ” as " veritable this fundamental insecurity must exist. But to this rubbish,” † and finally in October, 1859, just before subject we shall return later.
the publication of the “ Origin ” we find the following It is hardly necessary to remind any one familiar remark as the postscript of a letter to Lyell : “You with Mr. Darwin's works that he considered certain often allude to Lamarck's work ; I do not know what phenomena to be only explicable as the inherited you think about it, but it appeared to me extremely effects of increased use or disuse of particular organs. poor; I got not a fact or idea from it." I With Many of the phenomena of degeneration, for in- these very definite and strong statements of Darwin stance, in a useless organ, he thought were due to the before us we can hardly 'contend, I think, that he effects of disuse. He expressly states * that the borrowed his views about the inheritance of acquired working of this factor is always subordinate to natural characters from Lamarck. In his “Historical selection, and that in some cases its effects are de. Sketch," prefixed to the sixth edition of the stroyed by the latter ; but there is no doubt, as Mr. "Origin,” he calls attention to the “eminent serHerbert Spencer has shown, t that, as time went vice" done by Lamarck in “arousing attention to on, he attributed increasing importance to this the probability of all change in the organic world factor ; that he was, in fact, driven slightly from his being the result of law ;” (p. xiv.) but there is no original position by hostile criticism. Later in life, word of praise for that part of the French naturalist's too, he became convinced that the cumulative direct theory of evolution which coincides with some of effect of changed conditions had been important in
Darwin's own views. I do not think there remains a some cases, especially where partial or complete doubt that the “ trace of Lamarckism " often alluded isolation allowed them to have full effect. In a letter to as remaining in the Darwinian theory, is not to Professor Wagner in 1876, he goes so far as to Lamarckism at all, except in the sense that Lamarck say, “In my opinion the greatest error which I have advocated similar views. As I have said, at the committed has been not allowing sufficient weight to time when the "Origin" was thought out and the direct action of the environment, i.e. food, written, and for a long while afterwards it had climate, etc., independently of natural selection." never occurred to any one to doubt that acquired
But although Mr. Darwin believed in the trans- characters could be inherited, and it was natural mission by heredity of "acquired modifications,” I enough for Darwin to use this universally accepted think it is a mistake to suppose that he derived his factor to supplement natural selection. We find his belief from Lamarck's teaching. No one doubted, nearest approach to dogmatism on this subject : until quite cently, that characters acquired during “Changed habits produce an inherited effect, as in the life of the individual were hereditary equally with the period of the flowering of plants when transcongenital ones. Mr. Darwin found that he could
ported from one climate to another, etc.” § The not explain certain phenomena by natural selection, naturalness of such an occurrence being obviously and thought that they were best explicable as the taken for granted, there is in many cases hardly an result of increased use or disuse, etc. The explana- attempt at proof, and very seldom is the evidence for tion formed but a small part of Mr. Darwin's theory, and against the explanation given worked out and as it had of Lamarck's, but while it was scientifically weighed with the minute and painstaking care to the strongest portion of the Lamarckian doctrine of which we are accustomed in all Darwin's works. evolution, it was the weakest of the Darwinian. We I have insisted on these considerations because it know that Mr. Darwin did not estimate the “ Philo.
seems of very considerable importance to ascertain sophie Zoologique " very highly. Thus he says : “It Darwin's exact attitude towards the views in question, is curious how largely my grandfather, Dr. Erasmus how and why he acquired them, and what relation Darwin, anticipated the views and erroneous grounds they bore in his mind to the theory of natural of opinion of Lamarck in his ‘Zoonomia' (vol. i. pp. selection. And it seems nearly certain that, unlike 500-510), published in 1794.” ŞAgain, he remon
that great hypothesis, the inheritance of acquired strates with Lyell in 1863 for alluding to his (Darwin's) characters was used as an obvious supplemental views as “a modification of Lamarck's doctrine of
explanation, and that a doubt of the truth of its development and progression,” and remarks that fundamental facts never entered Darwin's head. “this way of putting the case is very injurious to its But I deny that Darwin “ partially retained the acceptance, as it implies necessary progression, and Lamarckian explanation," thereby deliberately
adopting any of the speculative “laws” of the * Loc. cit. p. 114, &c. + “Factors of Organic Evolution," pp. 32–33. “Life,” iii. P: 159.
* “Life,” iii. p. 14.
+ Ibid. ii. p. 29. "Origin,” 6th edition, Historical Sketch, p. xiv.
# Ibid. ii. p. 215.
"Origin," p. 8.
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 hereaster 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 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 manyto 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 palæontologists, (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 bold somewhat similar views. Then we have a class of biologists like Mr. Patrick Geddes, who believes in natural
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.l., 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,
It is collaterally interesting, however, to note that so late as 1881 Darwin was “staggered” (by Hoffman's experiments on the direct effect of conditions on plants) in his views about the increase of variability, especially in cultivated plants, through such direct effects. -"Lise,” iii. p. 345.
† Ibid. iii. p. 44.
* Reprinted as "The Factors of Organic Evolution.”
the main body of working biologists, who do lower animal creation, at least, albino varieties have not, perhaps, go so far as the Neo-Darwinians, begotten progeny with similar tendencies. Why, but whose continually enlarging experience of the then, seeing it is of such vital importance, has the wonderful and beautiful adaptations to be found in subject of white variations in the vegetable kingdom every nook and cranny of the organic world and con- been so monstrously neglected ? stantly coming to light in their studies-anatomical, I for one must object to the word albinism being histological, physiological, or bionomic-makes them used in reference to floral variations which assume a firm believers in natural selection, as overwhelmingly whitish colour. By an albino I understand an animal the most important cause of evolution, and gives them possessing white feathers, white fur, white hair, or a a reluctance-justifiable or the reverse-to place much white skin, with the addition of pink or red eyes. I confidence in such supplementary factors as those I freely admit in either instance the variation may be have mentioned.
the result of similar pathological modifications, but Lastly we have the extreme “Neo-Darwinians," even that hardly warrants a use of the same term in as Professor Ray Lankester has called them, whose
Were it so, we might with as good position may be summarised as follows. They reason term the sweat.glands of the human body assert :
stomata, or the system of tissues through which (1) That the inheritance of any character acquired nourishment is conveyed to the extremities of a plant by an individual during its lifetime has never been the alimentary canal. experimentally proved : (2) that hence we are not One cannot be too cautious in advancing opinions justified in explaining any of the facts of evolution by on a subject so wide in its range and fraught with so any process which involves such inheritance : (3) that many difficulties; and of course, not being a these facts can be as well or better explained by practical biologist, I dare not dogmatise in this case. natural selection and kindred selective processes in But to myself, as I presume has likewise been the conjunction with the effects of training during the case with a great many readers of SCIENCE GOSSIP, individual life-time than by the alleged inheritance of the question naturally suggests itself, “How best to acquired characters, and that hence the indirect account for these deviations!” Do they occur evidence for such inheritance can be refuted, and (4) through a modification of the pigment cells? Is there that the onus probandi rests, not on them, but on their an intensified oxidation of the chromule? Is there opponents, who would retain an unproved and un- really an absence in the pigment of certain elements necessary (though hitherto universally-accepted) essential to the normal colouring? Or are these factor, in our explanation of evolution.
variations the outcome of a progressive or retrogressive Professor Weismann, Professor Lankester, Professor development of colouring-matter ? Pertinent ques. Meldola, Mr. Wallace, and Mr. Poulton are examples tions these, although such as ought to be partly, if of some of the more distinguished of the Neo- not even wholly, met by the more advanced readers Darwinians.
of, and contributors to, these columns. Will they In subsequent papers we shall be chiefly occupied come to our rescue ? I am daily more and more in investigating the justification of their views.
convinced of the importance of the subject, and am certain many others will with myself feel grateful for
any light. THE WHITE FLOWER QUESTION.
This district is inordinately prolific in the way of By FRED. H. DAVEY.
white variations. From Bissoe my father has repeatT would indeed be passing strange if the interest- edly brought pure white specimens; of Calluna erica,
ing correspondence on this subject did not lead Erica cinerea, and E. tetralix, and a few beautiful to some profitable conclusion. It is one of the white heads of Centaurea nigra. From the Lizard branches of botany which has notoriously held the I have had huge bunches of Erica vagans brought background, notwithstanding the probabilities that it me, embracing every shade from snowy white to deep might ultimately throw valuable light on the origin purple. My father entertains no doubt at all on the of new varieties, and thus minimise the labours of plants he has seen producing white flowers year after the large and indefatigable band of biologists who year. Some of them he has carefully watched for give their whole energies to a solution of the problem. upwards of twenty years without being able to detect Albinism in the animal kingdom, more particularly the remotest disposition on their part to return to in the genus homo, has long been an interesting field the normal colour. Erica ciliaris, on the contrary, of labour to scientists, and from all accounts has led never produces in this locality any but the rich pink to good results, so far as it has been proved albino flowers. varieties may at times possess the power of trans- The most peculiar variation coming under my own mitting their peculiarities to their offspring. I don't notice was a low, dwarf-like variety of Wahlenbergia mean to assert it is an established fact that albinism hederacea, bearing elegant white flowers, if anything in the human family is hereditary. But I do say it is a little more bell-shaped than those of the type-form. now beyond the range of probabilities that in the The plant cropped up in quantities some five years
ago in a small bog close by, and continued to thrive The celebrated collection of recent shells formed there up to last summer.
What struck me as the by the late Sir David Barclay, Bart., was sold by most remarkable feature of the case, was that the little auction at Messrs. Stevens' Rooms, London, on the pigmy grew in a straight line across the moor, at no 6th of July and three following days. The catalogue part spreading more than three or four feet. It was compiled by Mr. Hugh Fulton contained particulars a pretty sight to stand at one end and trace this of 1,200 lots, which included a number of extremely dainty morsel right across-here just peeping over rare species, also many type specimens. The the trailing pennywort, and there over-topped by the following are some of the highest prices realised for lesser skull-cap-and then to compare it with the single specimens :-Voluta aulica, £10; Murex more elegant trailing branches and delicate pale-blue Barclayi, £9 10s. ; Marginella mirabilis, £6 105. ; flowers of the normal plant which blossomed profusely Strombus taurus, £ 5 10s. ; Conus crocatus, £5 10s. ; all round.
Cyclostoma formosa, 64 ios. ; Cypræa vicallosa, 63; In addition to the plants mentioned we have Scalaria decussata (two specimens), £4 5s. noticed white varieties of Ranunculus ficaria, Aquilegia vulgaris, Viola canina, Polygala vulgaris,
A DEEPLY thoughtful, and highly interesting
address is that of Dr. A. Leifius, delivered before Geranium molle, Erodium maritimum, Sedum anglicum, Epilobium montanum, Valeriana officinalis,
the Royal Society of New South Wales (London:
Kegan Paul & Co.). Jasione montana, Primula vulgaris, Polemonium cæruleum, Symphytum officinale, Myosotis palustris, DR. J. E. TAYLOR has just published verbatim Digitalis purpurea, Veronica chamædrys, Pedicularis the “Story of the Felixstowe Crags ” (illustrated), as sylvatica, Thymus serpyllum, Prunella vulgaris, told by him to a public audience at Felixstowe on Ajuga reptans.
Wednesday, July 29 (Ipswich : “East Anglian Daily This list is a very significant one, and, if Grant Times" Office, price sixpence). Allen's theory of progressive colour development goes
The second quarterly number of “ The Concholofor aught, argues conclusively a movement on retro
gist” (edited by W. E. Collings) is even better than gressive lines. It will be noticed that in this list, as
the first. well as in the one submitted last month by E.
It cannot fail to prove a welcome guest
among all interested in Conchological subjects. Armitage, only two plants with yellow flowers figure as sporting into white. In his progressive colour. The Report of the Botanical Exchange Club for scale, Mr. Allen gives yellow, white, red, purple, 1890 (Manchester, Jas. Collins & Co., King St.) lilac, mauve, violet, and blue; white being an is as valuable an accession to our botanical literature improvement on the yellow, red on the white, etc. as usual. No English botanist should be without it. Our two lists show a remarkable preponderance of
The third number of the “Mediterranean Naturalblue over the yellow, and of red over the blue,
ist" demonstrates that a welcome and useful periodical driving one to the conclusion that as red is an im.
has joined our ranks. provement on white, and blue is the highest stage of development, white variations from the type indicate DR. C. W. RILEY'S “Report of the Entomologist a retrogressive rather than a progressive development for 1890,” is even more readable and suggestive than of colouring-matter.
is usual with this distinguished entomologist's “ReOf course these are merely a few suggestions. I. ports.” may be right or wrong in assuming the subject to be
The “Garner" is now amalgamated with the of vital importance, or in objecting to the word
“ Naturalist's Gazette," and both in the new form albinism being used in reference to this subject. I
are published at one penny monthly. may be equally right or wrong on the progressive or retrogressive colour theory, or in my assumptions on We have received a most interesting and thoughtthe oxidation of chromule, on the absence or presence ful brochure, by F. Howard Collins, on of certain elements in the pigment, or in the modi- Diminution of the Jaw in Civilised Races, an Effect fication of the pigment cells. Be that as it may, of Disuse.” Of course, the author refers to eatingthese suggestions may help to focus our attention, not to politics or "social" subjects. and thereby enable us to deal practically with the problem.
Sir Geo. B. AIRY, late Astronomer Royal, is the Pousanooth, Perran-ar-worthal, Cornwall.
doyen of British science. He has just entered his ninety-first year, and appears to be as bright and
chippy as ever. SCIENCE-GOSSIP.
AFTER re-consideration the President of the Board We have received a reprint from “ Inventions,” of Trade has granted a licence to the British Institute giving an account of Mr. James Nelson's ingenious of Preventive Medicine to register the institution as a “Calculating Dial,” as furnishing a ready means for limited liability company with the omission of the calculating figures in commercial business.
word “ limited.” The licence, however, is not to be