I04 



NATURE 



[Nov, 29, 1888 



it is hopeless to continue discussion with so extraordinary a dis- 

 putant. Indeed, as he had published this statement in bald and 

 obvious contradiction to all my writings, nothing more remains to 

 be said : I simply challenge justification as plainly impossible.^ 



The next point in Mr. Dyer's criticism is where he says that 

 if a large proportional number of specific differences are, as I 

 allege, useless, this "would be quite as effective as proving 

 the proposition universally in inflicting a deadly blow on the 

 Darwinian theory, the very essence of which is that specific 

 differences must be advantageous." Now this I deny in toto. 

 It is no part of the essence of Mr. Darwin's theory to assume 

 that all specific characters must be advantageous, nor does it 

 even belong to this theory to decide in what proportion as to 

 number advantageous characters stand to indifferent ones. 

 Without going over the ground already traversed with regard 

 to this matter in my previous letter, perhaps it may produce 

 some effect on Mr. Oyer's mind if I quote Mr. Darwin's own 

 opinion upon the subject. After stating what would be " abso- 

 lutely fatal " to his theory, he proceeds (italics here and else- 

 where mine), " I fully admit that many structures are now of no 

 use to their possessors, and may never have been of any use to 

 their progenitors. . . . It is sea' cely possible to decide hovi mMch. 

 allowance ought to be made for such causes of change as 

 the definite action of external conditions, so-called spontaneous 

 variations, and the complex laws of growth ; but, with these 

 important exceptions, we may conclude that the structure of 

 every living creature either now is, or formerly was, of some 

 direct or indirect use to its possessor" ("Origin of Species," 

 sixth edition, p. 160). Mr. Huxley expresses himself to exactly 

 the same effect in his recently- published obituary notice, where 

 he says that, so far as the theory of natural selection is concerned, 

 a species may present ^'' any mimhcr" of characters "which are 

 neither advantageous nor disadvantageous, but indifferent, or even 

 slightlydisadvantageous"(Proc. R.S., vol. xliv. No. 269, p. xviii.). 

 After all the controversy which I have had upon this subject with 

 Mr. Wallace, I am exceedingly glad to find Mr. Huxley speak- 

 ing out so " roundly " on the Darwinian side of it. Mr. Dyer, 

 indeed, still objects that he thinks " Mr. Huxley is disposed to 

 make too great concessions." Of course Mr. Dyer is entitled to 

 have his own opinion upon the matter ; but I submit he is not 

 entitled to set up this opinion as so authoritative that I am ipso 

 facto bound to accept its statement as constituting the very 

 essence of the Darwinian theory. No doubt "with regard to 

 plants" he is "competent to speak"; but he must surely be 

 aware that other botanists who have more thoroughly considered 

 this question are dead against him in his general conclusion. 

 In particular, the late Prof. Nageli made this subject the matter 

 of a careful inquiry " with regard to plants," the result of which 

 was very materially to influence the judgment of Mr. Darwin. ^ 



Next, Mr. Dyer says that because I am not what he calls a 

 "practised naturalist," my "method is the very inverse of that of 

 Mr. Darwin." Now, without at all recognizing Mr. Dyer's 

 right to lecture in this way on the subject of scientific research, 

 I may nevertheless refer him to the history of every other 

 theory which has ever been published with reference to genera- 

 tion, from the "provisional hypothesis" of pangenesis by 

 Darwin himself, through the plastidule of Haeckel and the 

 idio-p!asma of Nageli, to the keim-plasma of Weismann. In 

 all these cases the "method" has been the same as mine — 

 viz. to collate the known facts bearing on the principle suggested, 

 and to leave for future work such experimental verification as 

 may be possible. Moreover, even the theory of natural selec- 

 tion (to which, I suppose, Mr. Dyer more especially alludes) 

 was established by general reasonings from the bringing together 

 of facts already known ; ^ and when we remember the much 

 greater importance of this theory, as well as the whole change 



' In another part of his letter Mr. Dyer says that my theory of physiological 

 selection " shrivels up the part played by natural selection to very small 

 dimensions." Here, again, I can only request that some explanation shculd 

 be given of the process of reasoning whereby my critic has arrived at this 

 most astonishing conclusion. 



^ " I now admit, after reading the es?ay by Nageli on plants, and the re- 

 marks by various authors with respect to animals, more especially those re- 

 cently made by Prof. Broca, that in earlier editions of my ' Origin of Species ' 

 1 perhaps attributed too much to the action of natural selection. . . . I did 

 not formerly consider sufficiently the existence of structures, which, as far 

 as we can at present judge, are neither beneficial nor injurious ; and this I 

 believe to be one of the greatest oversights as yet detected in my work." — 

 " Descent of Man," second edition, p. 61. See also, f>r emphatic passages to 

 the same effect in the " Origin of Species," sixth edition, pp. 171, 176, 421. 



3 " Belief in natural selection must at present be grounded entirely on 

 general considerations, .... and chit fly from this view connecting under 

 an intelligible point of view a host of facts."— -Letter of Darwin to Bentham, 

 " Life,' ' &c., iii. p. 25. 



of thought which it has produced with reference to the general 

 doctrine of evolution, I cannot feel that, relatively speaking, I 

 was over-precipitate in publishing my views on physiological 

 selection. 



Further on Mr. Dyer objects to my names for the principle in 

 debate — j.i?. " physiological selection " and " .^segregation of the 

 fit "—and says he is "surprised that Mr. Romanes has taken so far 

 no notice " of this objection as originally presented in the Times. 

 But here again "the demon of inaccuracy" pursues him. In 

 my general reply to criticisms, already referred to above, and 

 prominently so in these columns at the time, I fully considered this 

 objection; and therefore, if on my side there were still any room 

 left for "surprise," I might have here expressed a certain degree 

 of wonder that before writing the letter which he has now 

 published he should not have taken the trouble to read the 

 author whom he is somewhat intemperately attacking.^ 



In point of fact, however, his attack is everywhere delivered 

 with so complete an absence of judgment, as well as of informa- 

 tion on what he is writing about, that it amounts to a mere 

 hitting at random. This, 1 think, I have now sufficiently proved. 

 Nevertheless, although truly "rather late in the day," I com- 

 mend to his consideration my article in the Aineteenth Century 

 of nearly two years ago, as disposing still more effectually than 

 space will here permit of every one of his general statements and 

 detailed objections. T may add that the bias shown by thus re- 

 peating borrowed criticisms, without first consulting my answers, 

 quite deprives his opinion, in my estimation, of the weight to 

 which I might otherwise have felt that it was entitled. 



In conclusion, it is useless to conjecture with Mr. Dyer what 

 Mr. Darwin would have thought of physiological selection as 

 a theory ; and I have already given my reasons for holding it 

 improbable that he ever considered it (Nature, vol. xxxiv. p. 

 545). On the other hand, I should like to remark, that although 

 what he complained of as " the great power of steady mis- 

 representation " ^ has seriously prejudiced the theory in this 

 country, such has not been the case abroad, where in many 

 quarters it has been received with unqualified favour. This 

 remark — which applies to botanical as well as zoological au- 

 ti-.ority — is added merely in order that the theory may have fair 

 play. George J. Romanes. 



Geanies, Ross-shire, N.B., November 4. 



P. S. — Proofs of this letter have been accidentally delayed in 

 transmission. — G. J, R., Edinburgh, November 22. 



Cleistogamy. 



I SHOULD like to add a few words to the extract from the 

 minutes of the Scientific Committee of the Royal Horticultural 

 Society, quoted in Nature, November 22, p. 86. The causes 

 of the cleistogamous condition of some of the plants mentioned 

 I would attribute to their stunted habit induced by mowing, 

 coupled with a relatively cold season. For, while some of them, 

 e.g. Cerastinni, Montia, and Alchemilla, xzxtXy open their buds, 

 the Veronica, Sagina, and Trifolium, are more inclined to do 

 so, if allowed to grow more vigorously, and if the temperature 

 be higher. Cleistogamy is of course only a relative quality. 

 Thus chick weed and spurry will open their flowers widely in hot 

 weather ; but are cleistogamous and abundantly self-fertile all 



' The fol'owing is what I said with regard to this criticism in the Nine- 

 teenth Century for January 18S7, and it leaves nothing further to be 

 said now: — "Ihis is a po.nt of no_ real importance, and I readily con- 

 cede that in some respects physiological isolation would be a better name 

 than physiological selection. The reasons which inclined me to adopt the 

 latter in preference to the former will be gathered from what has just been 

 said. If the theory is sound at all, a process of true survival takes place, 

 in seme cases of the primary [i.e. sexual], in other cases of those secondary 

 [i.e. morphological] specific characters which are capable of inducing the 

 primary ; and m either event it is only certain changes of character, i r par- 

 ticular variations, which are setected to survive as new species. Moreover, 

 the term physijljgical selection does not exclude the term physiological 

 isolation, any more than the term natural selection excludes the term sur- 

 vival of the fittest. . . . The ' fitness ' of the individuals affected is guaran- 

 teed by the fact of their having reached the breeding age. This latter point 

 is important, because Mr. Wallace accuses me of having lost sight of the 

 c insideration that my physiological variations must conform to the law of 

 natural selection. ... If these physiological varieties ever occur at all, ex 

 hypottiesi they must have sd far passed muster with respect to general fitness 

 as to be allowed to propagate their kind. It was for the sake of emphasizing 

 this feature of my theory that I gave the latter the alternative title of 

 ' segregation of the fit.' " 



^ "Origin of Species," p. 421. The whole paragraph, read in connection 

 with the present controversy, is cur.ously interesting, and to ine very con- 

 soling. Moreover, the scientific creed wh ch it rehearses is in every 

 particular identical with my own, while differing considerably from that o 

 my critic. 



