278 



NATURE 



[December 28, 191 1 



LETTERS TO THE EDITOR, 



[Tht Editor dots not hold himself responsiblt for opinions 

 txprtssed by his correspondents. Neither can he undertake 

 to return, or to correspond with the writers of. rejected 

 manustri'pts intended for this or any other part of NatUM. 

 No notice is taken of anonymous communications.] 



The Thames ValUy. 

 In th<? " Physical Geology and Geography of Great 

 Rritn'm." Sir A. Rnmwv rxpr#«*«#d •ome interesting 

 about til hetween 



t of the '11 ling to 



his \i.v., tltc Severn '...i.-' > ■• • ■ •••h "one of 



the oldest in the lowlands of "He considered 



that the s«Tondary strata to ti nst of that river 



originally drained into it, and that subsequent subsidence 

 altered their inclination to an eastward slope, causing the 

 waters to cut a new channel through the Oolites and Chalk 

 towards the cast, the direction in which the Thames flows 

 at present. This view, I believe, has never been favour- 

 ably entertained by other gi-ologists, owing to the absence 

 of corrolwrativc evidence of such a change in the dip of 

 thf" bods as Ramsay postulated. 



Nevertheless, I venture to ask consideration for a feature 

 in the fauna of the Thames Valley which is difficult to 

 reconcile with the belief that the Thames always flowed 

 eastward. 1 have called it a feature ; I should have said, 

 luoro correctly, the absence of a faunal feature character- 

 istic of other eastward-flowing rivers in England. 



In all the rivers between the Yorkshire Ouse and the 

 Norfolk Ouse is found that remarkable fish the burbot, or 

 eel-pout (Lota vulgaris), a creature remarkable not only 

 as being the only member of the Gadidae, or cod family, 

 known to inhabit fresh water (the North American 

 L. maculosa can be regarded only as a geographical 

 variant of the species), but also on account of its severely 

 restricted distribution in Great Britain. It seems fairly 

 safe to attribute the presence of this fish in the district 

 indicated to the former connection of these rivers — the 

 Trent, the Nen, the two rivers Ouse, &c. — with the great 

 Rhine system at a time when the North Sea was a vast 

 plain, through which these streams found their way to 

 join the mighty river on its course to the Arctic Ocean. 

 Ihe burbot, I believe, abounds in the Rhine at this day ; 

 if, as is commonly assumed, the Thames was ever a 

 tributary of the Rhine, why does it contain no burbot? 



On the strength of a passage in Leonard Mascall's 

 " Booke of Fishing with Hooke and Line " (1590), I, in 

 common with many others, was led to believe that the 

 burbot did once inhabit the Thames ; but I think I can 

 now prove that we have been misled by a printer's or 

 writer's error. 



" There is a kind of fish in Holand [not the kingdom 

 of Holland, but the south-eastern district of Lincolnshire] 

 in the fenne-- beside Peterborrow, which they call a 

 poult ; they b<> !ike in making and greatness to a whiting, 

 but of the cullour of the loch [loach] ; they come forth of 

 the fenne brookes into the rivers there about, as in 

 Wandsworth river there are many of them. . . . They are 

 taken in welles [eel-baskets] and at waters [weirs] like- 

 wise. They are a pleasant meate, and some do thinke they 

 would be as well in other rivers and running waters, as 

 Huntingdon, Ware and such like, if those waters were 

 replenished as they may be with small charge. They have 

 such a plentie in the fenne brookes, they feed their hogges 

 ■ with them. If other rivers were stored with them, it would 

 be good for the commonwealth, as the Carpe which came 

 of late yeares into England. Thus much for the fenne poult. " 

 Now it was easy to suppose that when Mascall wrote of 

 the " Wandsworth river " he meant the Wandle, which 

 joins the Thames at Wandsworth. But if the passage 

 above quoted be read carefully it appears clear that he 

 was treating only of rivers in the fen district, and that he 

 referred, not to "Wandsworth on the Thames, but Wans- 

 ford on the Nen, a few miles west of Peterborough. This 

 explains the difficulty of understanding how a vigorous and 

 prolific fish, once inhabiting the waters of the Thames 

 Valley, and not depending, like the salmon, upon free 

 access to the sea, could have totally disappeared within 

 300 years. The burbot never inhabited the Thames system, 

 a fact which seems to support Sir A. Ramsay's doctrine 

 that the Thames formed originally part of the Severn 



NO. 2200, VOL. 88] 



I system, with a grneral flow from ea«t to west, while th« 

 ' basins of t and Yorkshire Ouse were connected 



, with the I, m. Herbert Maxwru.. 



' .Monrciiti, \\ li^uwnshire, December 20. 



The Inheritance of Mental Characters. 

 Sir H. Brvan Doskin (December 14, p. 310) thinks that 

 I am quibbling, and Dr. Rcid (ibid.) thinks that I am not 

 clear as to the nituation. I cannot .t • points. 



Suffice it to say ihat my clearly defir.' was and 



is to show, not that Prof. Pearson's st.-u'iii'.-ni quoted by 

 Dr. Reid was right, but that Dr. Rcid's condemnation of 

 it was wrong and misleading. 



A real ditficulty appears to me to lie in the fact that 

 different p«?ople use different names for the same thing, 

 and the same name for different things. No so-called 

 character is more than a potentiality in the fertilised ovum. 

 The result of the action of the environment is to ' 



successive stages in the development of these pot< 

 The potentialities, which are subject to variation- 

 be inherited, are, to me, the only true inborn ci 

 I gather from Dr. Reid's writings that this is sut. 

 his view. 



All the characters quoted from Prof. Pearson 

 tures of acquired and inborn elements. If the torc-arin 

 were never used from birth, it would develop no more 

 than it does in a case of infantile paralysis. If any two 

 children were given precisely the same amount of exercise 

 and of other factors in the environment which influence 

 the development of the potentiality, the development in 

 each would be different. The histories of those remark- 

 able families, the Jukes and Zeros, which produced an 

 enormous number of criminals in a few generations, are 

 well known. Some of the criminal members did not have 

 the same educational environment as their parents. The 

 character dealt with in the fore-arm measurements does 

 not include the presence or absence of the limb. It is 

 development dependent upon a potentiality and a similar, 

 but not identical, environment. Conscientiousness, as 

 dealt with by Prof. Pearson, is development dependent 

 upon the same factors. If it is contended that variations 

 in the environment influence the character, I agree, but 

 in the sense implied here both characters are certainly 

 inherited in the same way. 



Dr. Reid again quotes Prof. Pearson, this time as say- 

 ing that the characters with which he dealt were ** bred» 

 not created." I accept Dr. Reid's statement that the 

 meaning implied by " bred " is equivalent to inborn, and 

 by " created " acquired. Having made this quotation. Dr. 

 Reid asks: "Is potentiality meant here?" When I read 

 Prof. Pearsoii's Huxley lecture I certainly thought that it 

 was. " Geniality and probity and ability may be fostered, 

 indeed . . . but . , . their origin is deep>er down than 

 these things. They are bred, not created." Not only this 

 passage, but others, led me to believe that Prof. Pearson, 

 in saying that these characters are inherited, implied that 

 their origins, as distinct from acquirements, are inherited. 



Leaving speculations as to Prof. Pearson's private 

 thoughts, and as to how he intended his public statements 

 to be interpreted, may I pursue a more profitable course 

 in asking Dr. Reid for enlightenment as to what he 

 means? Dr. Reid's last letter gives me the impression — 

 I am very likely mistaken — that he considers educability, 

 as regards mental characters in man at any rate, as a 

 single potentiality for development, and that the kind of 

 stimulus or stimuli determines which, and to what extent, 

 characters will develop. Now, though I agree with Dr. 

 Reid that individual characters are less certainly inherited 

 than racial, I hold, and I think that he does so too, that 

 the former are the material from which natural selection 

 produces the latter. Unless each of the mental characters 

 is dependent upon a separate potentiality, we must con- 

 clude that a change took place whereby all the mental 

 potentialities were massed together ; for it is inconceivable 

 that the various adaptive instincts in the lower animals 

 could have evolved otherwise tlian separately. We are by 

 no means confined to pure instincts or to the lower animals. 

 It would doubtless be possible to teach a bulldog to point, 

 but it is certainly more difficult to teach bulldogs generally 

 to point than it is to teach pointers to point. It is also 

 usually more easy to bring a pointer of good ancestr>" to 

 a high state of efficiency with regard to his various and 



