248 



NATURE 



{Jan. 16, 1890 



can never be transformed into a mammal." There is something 

 more therefore than blind chance at work here. 



But within the limits, it is a matter of experience that every 

 possible variation may occur. If anyone will take the trouble 

 to examine the leaves of the ribbon-grass so commonly cultivated 

 in gardens, he will find it impossible to obtain any pair in which 

 the green and white striping is exactly alike. If it were pos- 

 sible to raise to maturity all the progeny of some prolific organ- 

 ism, the same diversity (in different degree, of course) would 

 manifest itself ; but the whole group of variations in respect of 

 any one organ would obey Quetelet's law. When we attempt 

 to give some physical explanation of this fact, we know from 

 the objective facts which have been made out about fertilization 

 that, although the protoplasmic content of the fertilized ovum 

 is, in a general sense, uniform, its actual structure and physio- 

 logical components must be combined in as endless variety as 

 the green and white stripes of the leaves of the ribbon-grass. 

 If, with Prof. Lankester, we say that the combinations are 

 kaleidoscopic, I do not see that we go beyond the facts. And 

 it appears to me quite permissible to correlate the ascertained 

 variable constitution of the ovum arising from this cause with 

 the equally ascertained varying structure of the organism deve- 

 loped from it. 



Of the varied progeny, we know that some survive and others 

 do not. And what Darwin has taught us is, that the reason of 

 survival is the possession of favourable variations. The surviving 

 race necessarily differs somewhat from its progenitors, and Dar- 

 win has further stated that it is probable that by the continued 

 repetition of the process all the diversity of organic nature has 

 been brought about. 



The area of fortuity is narrowed down therefore, on this point 

 of view, to the variable constitution of the individual ovum. 

 And it is upon the recognition of this fact, for which there seems 

 to be good scientific evidence, that the Duke of Argyll founds his 

 charge that the neo-Darwinians make fortuity their idol. The 

 reason appears to be that it comes into collision with teleological 

 views. But such collisions are no new event in the history of 

 the biological sciences. And teleology, like a wise damsel, has 

 generally, though temporarily ruffled, managed to gather up her 

 skirts with dignity and make the best of it. For some element 

 of fortuity is inseparable from life as we see it. It is at the 

 bottom one of the most pathetic things about it. Nowhere is 

 this more vividly portrayed perhaps than by Addison in the 

 "Vision of Mirzah." Yet I do not remember that anyone was 

 ever so unwise as to taunt Addison with making fortuity his idol. 



But, philosophically considered, what is gained by this tenacity 

 about out-works ? I reply, exactly as much as was gained by 

 the tenacity of the Church in respect to the geocentric theory of 

 the planetary system. Scientific men cannot be stopped in the 

 application of their best ability to the investigation of Nature. If 

 their conclusions are false, they will detect the falsity ; if true, 

 they will not be deterred from accepting them by some ci priori 

 conception of the order of the universe. It is not justifiable to 

 say that this is due to any devotion to such an empty abstraction 

 as fortuity. No scientific man is, I hope, so foolish as to suppose 

 that, however completely mechanical may be his Qonception of 

 Nature, he is in any way competent to account for its existence. 

 The real problem of all is only pushed further back. And the 

 Duke of Argyll's difficulty resolves itself into the old question, 

 whether it is more orthodox to conceive of the universe as an 

 automatically self-regulating machine, or as one which requires 

 tinkering at every moment of its action. 



It may be replied that this is all very well, but that it is not 

 the way the neo-Darwinians state their case. I may be, there- 

 fore, excused for quoting some passages to the contrary from 

 Weismann's " Studies in the Theory of Descent " : — 



"This conception represents very precisely the well-known 

 decision of Kant : ' Since we cannot in any case know a prioj-i 

 to what extent the mechanism of Nature serves as a means to 

 every final purpose in the latter, or how far the mechanical ex- 

 planation possible to us reaches,' natural science must every- 

 where press the attempt at mechanical explanation as far as 

 possible " (p. 638). 



Further, he quotes from Karl Ernst von Baer : — 



"The naturalist must always commence with details, and may 

 then afterwards ask whether the totality of details leads him to 

 a general and final basis of intentional design " (p. 639). 



Again, he says : — 



" We now believe that organic nature must be conceived as 

 mechanical. But does it thereby follow that we must totally 

 deny a final universal cause ? Certainly not ; it would be a 



great delusion if anyone were to believe that he had arrived at 

 a comprehension of the universe by tracing the phenomena of 

 Nature to mechanical principles" (p. 710). 



In truth, this revolt of teleology against Darwinism is a little 

 ungrateful. For, if Darwinism has done anything, it has carried 

 on and indefinitely extended its work. In the last century, 

 teleology was, it seems to me, a valuable motive-power in bio- 

 logical research. Such a book as Derham's "Physico-Theology " 

 (171 1) may be read with interest even now. I well remember 

 that my first ideas of adaptive structures were obtained from the 

 pages of Paley. Thirty years ago I do not know, except from 

 them and the notes to Darwin's " Botanic Garden," where such 

 information was to be otained. The basis of research was, 

 however, too narrow to continue ; it did not look beyond the 

 welfare of the individual. The more subtle and recondite springs 

 of adaptation opened up by the researches of Darwin, which look 

 to the welfare of the race, were not within its purview. Conse- 

 quently it dried up, and virtually expired with the Bridgewater 

 Treatises. 



To return, however, to the Duke of Argyll. " Neither 

 mechanical aggregation, nor mechanical segregation, can possibly 

 account for the building up of organic tissues." Who has said 

 they did ? The Duke has entirely misunderstood the matter. 

 Prof. Lankester never suggested that it was possible to put so 

 much protoplasm into a vessel, and shake out a cockatoo or a 

 guinea-pig at choice. His image of the kaleidoscope had 

 nothing to do with the building up of organisms, only with the 

 varied combination of the elements known to take part in the 

 formation of the fertilized ova from which organisms originate. 



I am not sure that I perfectly comprehend what follows. 

 Perhaps some further emendation than that already published is 

 needed in one of the sentences. But it seems evident that the 

 Duke is re-stating his old doctrine of "prophetic germs." He 

 has already defined what he means by these (Nature, vol. 

 xxxviii. p. 564). "All organs," he says, "do actually pass 

 through rudimentary stages in which actual use is impossible." 

 Here, again, as in the case of the transmission of acquired 

 characters, what one wants is not a reiteration of the assertion, 

 but some definite observed evidence. For the production of 

 this, if only in a single instance, Prof. Lankester pressed the 

 Duke more than a year ago (Nature, I.e. p. 588). None, 

 however, has as yet been forthcoming ; and it appears to me 

 that it is not permissible to persist in statements for which he 

 does not attempt to offer a shadow of proof. 



The Duke exults in a very amazing fashion over what he 

 strangely calls Prof. Lankester's admission that " natural selec- 

 tion cannot account for the pre-existence of the structures which 

 are prescribed for its choice." I am afraid I have already tres- 

 passed on your space too much with quotations ; but 1 have 

 done so in order to show, in some measure at any rate, what is 

 the consensus of opinions amongst students of Darwinism ; and 

 I must answer the Duke with one more from Prof. Huxley's 

 a dmirable biography. It is true that the Royal Society publishes 

 th ese things in the least attractive way possible ; but this par- 

 ticular paper could hardly have escaped attention, as it won the 

 notice and admiration of even a journal so little occupied with 

 scientific discussion as Truth. 



" There is another sense, however, in which it is equally true 

 that selection originates nothing. ' Unless profitable variations 

 . . . occur, natural selection can do nothing' ('Origin,' ed. I, 

 p. 82). ' Nothing can be effected unless favourable variations 

 occur' {I.e., p. 108). 'What applies to one animal will apply 

 throughout time to all animals — that is, if they vary — for otherwise 

 natural selection can do nothing. So it will be with plants ' (I.e. 

 p. 113). Strictly speaking, therefore, the origin of species in 

 general lies in variation ; while the origin of any particular 

 species lies, firstly, in the occurrence, and, secondly, in the 

 selection and preservation of a particular variation. CleaJness 

 on this head will relieve one from the necessity of attending to 

 the fallacious assertion that natural selection is a deus ex maehind, 

 or occult agency." 



And the Duke says he has been waiting for this for thirty 

 years. One can only wonder what Darwinian literature has 

 been the subject of his studies during that time. 



W. T. Thiselton Dyer. 



Royal Gardens, Kew, January 6. 



The Microseismic Vibration of the Earth's Crust. 



In Mr. White'sarticle on British earthquakes (Nature, Jan. 2, 

 p. 202) he refers to me as having diseovcrcd the microseismic 



