August 22, 1907] 



NA TURE 



4«7 



lion. For in place of instructing the angler in the art 

 of allurin(j river-fjsh of all kinds, this volumff, as, 

 indeed, is indicated in its supplementary title, tells him 

 only how to capture the wily trout. .Since, however, 

 this is, par excellenrc, the sfiortin^ fish of Ivn((lish 

 rivers, there may be some justification for thf; desig- 

 nation. The author h;is already published a more 

 ambitious work on irout-fishinjf, which has, we 

 believe, l>een well rereived by anglers; but that volume 

 is intended mainly for ihe Umefit of those who are 

 already experts in the gentle art, whereas in the one 

 now before us it is v<ught to instruct the beginner in 

 the elementary principles of trout-fishing. 



Mr, Hodi^son is evidently one of those who believe 

 that salvation is to l>e found otherwise; than by " dry- 

 fly " fishing; and a considerable pfjrtion of his work 

 is accrjrdingly devoted to oth'-r methf^s, inclusive of 

 spinning with minnows, and luring with the luscious 

 wasp-grub. That the author will not please every 

 angler in all details may be regarded as a matter of 

 courvf; but, speaking generally, he seems to have 

 treated his subject in a manner which ought to satisfy 

 those who are making their first essays at trout- 

 fishing. The book is well illustrated, and likewis" 

 contains a number of observations on the natural 

 history of the subject, and, indeed, on nature-study 

 generally. R. L. 



< U:\ETICS.' 

 'T^ HE last contribution to the fast-increasing pile 

 ■*• of Mendelian literature is unique. It is at once 

 the bulkiest, within th<- limits of two covers, that has 

 been made to this subj'-ct, and at the same time the 

 most condensed, the most varied, and the most valu- 

 able. 



The third International ('onferencc on Genetics, held 

 under the auspices of the Royal Horticultural .Societv, 

 and under the presidenr y of Mr. Bateson, was a verk- 

 able Mendelian orgie. 'Ihe history of all new theories 

 is the same. They are judged not vj much on their 

 own merits as on the number and variety of natural 

 processes, pret'iously unintelligible, which they ex- 

 pbiin. 'ITie result of the publication of the '• Origin of 

 -Specie-s " was, as Mr. I{atesf>n has (x^inted out, the 

 distraction of the attention of biologists from the 

 process of evolution iis'-lf and its diversion into the 

 hitherto dry channels of paleontology, classification, 

 embryology, comparative anatomy, and distribution. 

 It was not until the end of the nineteenth century that 

 men returned to the study of evolution. The relation 

 between man and a new theory is the same as that 

 between a child and a new tov. When we first get the 

 toy we are occupied in playing with it in every pos- 

 sible way, and as often and as much as we ran.' But 

 when all lejritimate v^urcfs of inte-res* h-iV- l^een 

 tapped, we tire of playing with the toy and b<.-gin 

 to wonder how it works; and, to satisfy our 'urif/sity, 

 we pull if to pieces. The result of the attempt to 

 satisfy this curiosity in the case of Darwin's iheryry 

 was the growth of a conviction that natural seI/:ction 

 did not provide a sufTident explanatir^i of the diversity 

 of organic forms. The hisU^ry of Mcndelism has br-en 

 like that of Darwinism. The flood of energy let Ictosc 

 by the re-discmery of .Mendel's papers has sjx-nt itself 

 rather in work based on the assumption that the inter- 

 pretation which Mendel put on the facts he discovered 

 was true than in the attempt to discover whether that 

 interpretation were true w not; and in <n:r '/rAn'um it 

 is right that this should be so. The m'^ely critical 

 spirit is a barren one. The enthusiasm of the kind 



> Rtfnn of Ifce TJwd InitnmfjnaX Caaftrtaoc, >&-j6. on Cimtto. 

 VjSuA br Kar. W. Wilki. Kp ,H. (PnMnl <br the Ror»i H<rtiei>!t«»l 

 Soatty ly Spatutmiy^iK »« 0„, Ltd., u-^.) Price ijj, 



NO. 1973. VOL. 76] 



which follows the birth of a new theory such as 

 Darwin's or Mendel's has been as productive of dis- 

 covwy in the cawr of the L-ilter as it was in that of 

 the former, .At the same time, we should not forget 

 that .Mendelism is now in the stage in which Darwinism 

 was before it was subjected to the process of being 

 overhauled; and though we may f^frrhaps be right in 

 holding that criticistn is barren o( discovery, we should 

 guard against the possibility of entering that frame 

 of mind which regards rriticism as blasphemy. 

 .Mendel's [>fras have alnady been called tiassiial ; and 

 it is a very remarkable fact that no one has ref>eated 

 .Mendel's cxi>'rriments with the deliUrrale intention of 

 testing the Mendelian interpretation of the results, 

 I'eople sjMjak as if .Mendel got to the fxjtiom of the 

 inheritance of roundness and wrinkledness, yellowness 

 and greenness, and as if there was nothing more to 

 be said on the subject. On p, 88 of the rejjort before 

 us there is a table exhiWting the result of crossing a 

 yellow with a green pea to the fifth generation. The 

 proportion of pure yellows, impure yellows and greens 

 is given both for the fourth and for the fifth gener- 

 ation as 1 : 2 : I, and it is slated on the bottom of p, 88 

 that this jjroccss of segregation will f><- continued 

 "practically for ever," It is highly probable that the 

 three categories do form respectively 25, 50, and 25 

 per cent, of gen'rrations four and five; but Mendel 

 nei'frr published any figures which prove this to be so, 

 .Ml he said was ; " The prf/fx^rtions in which the 

 descendants of the hybrids dev'elop and split up in the 

 first and vrcond generations presurn;ibly hold gfX(d for 

 all subsequent progeny. Ivxp'.-riments one and two 

 have already b<;en atrr'utA through six generations, 

 three and s<;ven through five, and four, five, and six 

 through f</ur, thesf; exf>erim'mls being continued from 

 the third generation with a small number of plants, 

 and no departure from the rule has been furratfitihle." • 



We offer no ap<jlogy for ad/jpting this critical attitude 

 towards .Mendelism, Thf-re is plenty of admiration 

 for " Mendel's incomparable aehievement," and we 

 share it; but we do not find it imf>ossihl/: to combine 

 it with a suspicion that .Mendel's interpretation of his 

 results tnay not have be<;n right after all. 



The ri-\K>rl is. of cours'r, aWdulely indiscmsable to 

 every student of genetics, whether his int*rest is 

 purely scientific or purely horticultural, or both. The 

 keynof- of the cf^iference was stru^-k by a fit^Unic 

 of the marriage bells of .Science and Practice, We 

 could have no i>etter guarantee that their union will be 

 fc-rtile than that their hands w<:re joined by the Rev, 

 W. Wilks, who has earned the gratitude of every 

 study of heredity l»y '-Jiilinfi this refxtrt. and of 

 evt-ry lov-r - ' "- •■ '--'by creating •^■'- '^'-=-' - • - ■ 



JVOT£S. 



Pbof. li. l.e CiUTELics ha« been oflicially nominated 

 pTKietsor of cbemiMry at the Tari* Faculty of .Scien<e« 

 in kuctession to the lau: Prof. Henri Mointan. 



I; hat b*«^ decided by the Paris Municipal C'ntn'H Ui 

 perpetuate the nwmory of Prof. Berthelot by r'-.-naming 

 the Place du ColK-ge de France the Place .Marcelin 

 Bert helot. 



We r-grH to have to record that Prof. Kar! Vogrf, 

 dirertor of the Astrophysical Observatory at Potsdam, 

 di<^ on .Aujjuft 13. 



We regrnt to have to announce the death of the Rev. 

 Dr. John Kerr, F.R.*? , f'>rfr»r!r !'-*';rT on mathematif* 

 in the GIatgo». .' "ge, 



' 'naii*H»tK*jn^~ ;'' 57' Tb«or»3[««»l 



Bwy be c^/Mitu>d, ;■ ■.. i2r« C(f 0*<waJ4'* 



Kialiiktr J:r txaklen '//:..: /. , ,1 ■.-/:.-,-.<_ tef Plxtturofa) bndcA 

 Pncc iwtmk. 



