September 15, 1923] 



NATURE 



!9i 



Letters to the Editor. 



[The Editor does not hold himself responsible for 

 opinions expressed by his correspondents. Neither 

 can he undertake to return, nor to correspond with 

 the writers of rejected manuscripts intended for 

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The Inheritance of Acquired Characters in Alytes. 



For those who are not concerned with the details 

 of this debate I suppose that the critical sentence in 

 Dr. Kammerer's letter (Nature, August i8) is that 

 in which he expresses himself as follows : "I willingly 

 admit that the traditional explanation of the pads, 

 namely, that they are produced by friction with the 

 skin of the female, may possibly be a fable," adding 

 references to passages in which he had already 

 discussed alternative hypotheses. But those alter- 

 natives were ultimately rejected, and his final 

 judgment was that until the assumption that the 

 pads arise through functional adaptation can be 

 replaced by a better, it remains the only acceptable 

 account.^ Remarking that the alleged nuptial pads 

 vaa^Y possibly be due directly to life in water and not 

 an adaptative response, he now tells us that the 

 relevance of his observation to the theory of heredity 

 is in either alternative the same But is it ? 



The heavy task of searching for evidence of heredit- 

 ary transmission of acquired characters has clearly 

 been undertaken in the single hope, forlorn indeed, 

 but undying, that the difficulty created by the exist- 

 ence of the adaptative mechanisms might be removed. 

 They constitute a very grave difficulty in all theories 

 of evolution. Various evidence, mostly ambiguous 

 but as a whole significant, does suggest that in special 

 cases, by violent treatments, the germ-cells of animals 

 may be affected, more or less injuriously, and that 

 the consequences may persist at least for some 

 generations ; but that does not help us with the 

 problem of adaptation. Dr. Kammerer's admission 

 would relegate the Alytes pads to that class of 

 phenomena. Had this been all that was claimed, I 

 should have felt some interest in the matter, but less. 



The significance of the story is now reduced. In 

 190Q we were told that nuptial callosities appeared on 

 the thumbs of treated males, and that all the males 

 of the " F4 " generation had them. The claim that 

 this was a true adaptation was made without any 

 qualification whatever. This led to my request 

 (made privately in 1910, published in 191 3) that a 

 specimen should be produced. In 1919 we hear for 

 the first time that the swellings appear in various 

 other regions of the arms. When at length a specimen 

 is produced, I find it mounted to display a dark 

 thickening on the palm of the hand, a place which, 

 unless I am mistaken, had not previously been specified. 

 That this was the structure to which Dr. Kammerer 

 particularly wished to direct our attention appears 

 also froni the fact that the new photograph sent to 

 Prof. -MacBride, which I have not had the privilege 

 of inspecting, was made from it. So far as I am 

 aware, this is the only specimen ever exhibited 

 pubUclv. 



Dr. Kammerer complains that I did not at the 

 Linnean meeting produce " a single one of the many 

 objections " alleged in my letter of June 2. His 

 memory is at fault. My chief objection was the 

 position of the pat! on the palm. Any one who 

 attended the meeting will know that I directed very 

 prominent attention to this feature. To make my 



' 1919, p. S'^'S'- " I'-'vor also unsere .Xi ' ;■ I'libiklung 



geschehe diinJi fiink'iiiiillr Anpassung, duii '/i wtTden 



kann, blcibt sic die i iiuiy .ik/.optable." 



NO. 281 I, VOL. I 12] 



objection clear and conspicuous I asked in German : 

 " has Mdnnchen uniarmt sein Weihchen — so — [turning 

 the backs of my hands inwards] — nicht ? " To which 

 Dr. Kammerer as I thought nodded assent. No one 

 can have forgotten that the next speaker took me 

 to task for this, saying by a slip, induced I suppose 

 by what he had seen of the specimen, that " of 

 course " the common toad clasps the female with the 

 palms towards her. 



Why Dr. Kammerer should think that in writing 

 of his diagrams I had in mind a book of Plate's (which 

 I hear of for the first time), I cannot imagine ; for 

 I added the exact references to his own paper of 1909, 

 Figs. 26 and 26a. The pictures which I threw on the 

 screen, illustrating the fantastic story of MendeHan 

 segregation in respect of the modified habits, will also 

 be found in his paper 12 Flugschr. d. Deut. Ges. /. 

 Zuchtungskunde, 1910, and again in Natur, Munich, 

 December 12, 1909, papers to which all readers 

 desiring to see the prodigious scope of the original 

 claims should refer. A more detailed though un- 

 illustrated account appears in Mendel Festschr., 

 Briinn, 191 1. 



I do not propose to rebut the minor allegations made 

 by Dr. Kammerer. Several of these would not have 

 been made had he seen my letter in Nature of July 3, 

 1 9 19. The answers to the rest will be evident to 

 those who have followed the discussion. 



The question remains, what is the real nature of 

 the swellings in the animal exhibited ? That on the 

 palm did not look Hke a nuptial pad. What there 

 may have been on the back of the hand I do not know. 

 I m'ade no statement about it, though Dr. Kammerer 

 says I did. I might no doubt have asked to see the 

 back, but I had no reason to suppose there was any- 

 thing more to see. The palmar mark was what we 

 were shown for our conviction. This looked so 

 unlike what I remembered of real Brunftschwielen 

 that I did ask in the discussion, " Wie wissen Sie, dass 

 sie Brunftschwielen sind ? " I knew our frog and 

 toad very well, and, of course, Lataste's drawings of 

 sections, but it was some years since I had looked at 

 other species. I thought that perhaps, where the 

 development is slight, as in Rana agilis, the external 

 appearances might be less unlike what I had seen 

 in the Alytes, but they are not. When with that 

 specimen fresh in mind I examined a series of nuptial 

 pads in various Batrachia I realised still more vividly 

 how widely the structure in the Alytes differed from 

 the real thing. In my letter, therefore, I laid stress 

 on the dissimilarity. 



Dr. Kammerer writes that his specimen was 

 examined out of the glass by Sir Sidney Harmer and 

 Mr. E. G. Boulenger, but we are not told whether 

 they are among the " dozens " now convinced. Mr. 

 Perkins states that " the epidermal spines are very 

 obvious in the intact specimen." He is the only 

 independent witness, of those whose opinions have 

 reached me, who claims to have seen anything 

 so definite. 



I have a strong curiosity to see this Alytes again. 

 Dr. Kammerer challenges me to supply him with 

 apparatus for the purpose of photographing it. I 

 will make a different offer. For the opportunity of 

 examining it at leisure in the British Museum, where 

 comparative series are available, or if preferred in 

 Prof. MacBride's laboratory, I am willing to pay 25/. 

 either to the Versuchsanstalt or to other appropri- 

 ate authority. Plenty of responsible people travel 

 between Vienna and London, and there should be no 

 difficulty in arranging for safe conveyance. 



W. Bateson. 



The Manor House, Merton, S.W.20, 

 August 26. 



