594 



NA TURE 



[October 22, i< 



•worker, they approach one or the other of these favoured 

 specimens. The types are thus in the highest degree 

 -arbitrary and accidental, as is also, it must be confessed 

 (though in a less degree), the selection of other specimens 

 to be associated with them. 



" It seems to me certain that we are rapidly nearing 

 the time when our ever-increasing collections, revealing 

 as they do the infinite grades of variation presented by 

 living organisms — especially by stock or colony-forming 

 animals, such as corals, in which the varying factors are 

 doubled — will compel us to break loose from the restraint 

 of the Linnean 'species.'" 



Finally, the book is well printed, and the thirty collo- 

 type plates admirably illustrate the fades of the coralla. 

 Mr. Bernard has wisely added three lithographic plates 

 in which are represented carefully drawn details of a 

 typical calicle of most of the species. 



OUR BOOK SHELF. 



A Compendium of General Botany. By Dr. Max 



Westermaier. Translated by Dr. Albert Schneider. 



Pp. X -t- 299. (New York : John Wiley and Sons. 



London : Chapman and Hall, Ltd., 1896.) 

 In this book Dr. Westermaier has attempted to present 

 -an account of plants based on the lines indicated some 

 years ago by Schwendener. But so far as English 

 students are concerned, we cannot help thinking that he 

 has rather fallen between two stools. The beginner, on 

 the one hand, will find the book somewhat too advanced 

 for his use ; whilst on the other, a student who has already 

 acquired some knowledge of the science, will discover 

 that in the methods of dealing with some parts of his 

 subject, Dr. Westermaier is rather one-sided. Thus, in 

 discussing the factors operative in effecting the ascent of 

 sap, a sketch is given of the views advocated by the 

 author and by Schwendener, almost to the exclusion of 

 those of other investigators ; and we certainly cannot 

 accept the conclusions as affording an "authoritative 

 final explanation " of the process. 



Notwithstanding, we are ready to admit that the book 

 possesses some good points, and that it is interesting and 

 «ven suggestive in places. But it scarcely deserves the 

 somewhat ambitious title of "Compendium of General 

 Botany." 



The Testimony of Science to the Deluge. By W. B. 



Galloway, M.A. Pp. viii -(- 166. (London : .Sampson 



Low, Marston, and Co., Ltd., 1896.) 

 It is impossible to treat this book seriously. Such as 

 it were common enough forty or fifty years ago, but we 

 had hoped they had gone the way of the dodo. They are 

 •compounded after the following recipe : To the narrowest 

 views in theology, add a general ignorance of the 

 principles of inductive reasoning, collect a number of 

 scraps from scientific books, mainly those written when 

 geology was in its infancy, or if not, carefully separated 

 from their context ; stir all together into a hopeless con- 

 fusion, and serve up with a sauce of pious intention 

 flavoured by some inappropriate quotations from Scripture. 

 Mr. Galloway is one of the stalwarts ; he will be content 

 with no local deluges ; he will not let us off" a square yard 

 of the flood's extent, or a foot of its depth, except perhaps 

 in equatorial regions. This cataclysm produced the 

 rounded and scored rocks, the perched blocks and the 

 boulder-clays with the scratched stones. But he does 

 not explain to us why these products of a universal 

 deluge are restricted to certain parts of the earth, and 

 what were its leavings in districts where our so-called 

 glacial deposits are wanting. A deluge, however, must 

 have a cause. So Mr. Galloway finds this in a sudden 

 shift of the earth's axis of rotation, amounting to about 



NO. 1408, VOL. 54] 



i8i° ; and he unearths some speculations by Dr. Halley, 

 fully two centuries old, in support of his hypothesis. He 

 tells us also much about terrestrial magnetism which does 

 not seem particularly applicable, but we find no explana- 

 tion of what caused the shift, no proof that the resulting 

 disturbances of water would be powerful enough to trans- 

 port heavy rock masses in an open country — particularly 

 when it is admitted that the axis may not have "jumped" 

 from one position to the other, but that " several rota- 

 tions of the earth would probably take place in the 

 progress of the change." Mr. Galloway cannot even cite 

 his authorities accurately. J. Evans (now Sir John) 

 becomes T. Evans, G. F. Browne's Ice-caves becomes 

 Brown's ley Caves, and so on. But it is waste of time 

 to criticise this book. We present its author at parting 

 with a motto which might have been printed appro- 

 priately on his title-page — " Deferar in vicum vendentem 

 thus et odores, Et piper, et quicquid chartis amicitur 

 ineptis." T. G. B. 



LETTERS TO THE EDITOR. 



[The Editor does not hold himself responsible for opinions ex- 

 pressed by his correspondents. Neither can he undertake 

 to return, or to correspond with the ivrilers of, rejected 

 manuscripts intended for this or any other part of Nature. 

 No notice is taken of anonymous coinnuinications.\ 



The Utility of Specific Characters. 



Absence from England has prevented my taking part in the 

 discussion on this subject. At this stage I only desire to say 

 that I quite agree with Prof. Ray Lankester, as I stated at the 

 meeting of the Linnean Society, with respect to the contention 

 that the specific characters of the systematist are not neces- 

 sarily those upon which natural selection has directly acted in 

 bringing about the specific dift'erentiation. These e.tternal 

 visible or measurable characters may be, and I believe often are, 

 the outward expression of internal differences of constitution 

 with which the external characters are correlated. In entering 

 the lists at this late period, I am, however, mainly prompted by 

 an omission on the part of Prof. Weldon to strengthen his own 

 case by an argument which appears to me to be quite legitimate. 

 The point at issue is whether the results of his laborious and, in 

 my opinion, most valuable measurements of crabs, are to be in- 

 terpreted as demonstrating the action of selection, or simply as 

 revealing a law of growth. It might be imagined that if the 

 latter alternative proved to be the correct interpretation, the 

 case for selection falls to the ground. I do not take this view of 

 the work, and, as a member of the Royal Society Committee 

 concerned with the investigation, I am glad of the opportunity, 

 afforded by the discussion in these columns, of giving expression 

 to the idea which I have always entertained on this point, for 

 whatever that idea may be worth. If future observation should 

 show that there is no selection at work upon the young stages, 

 weeding out the individuals whose breadth of carapace falls 

 below a certain standard, but (according to the alternative) that 

 the individuals get broader as they grow older, then it appears 

 to me that the measurements may still be interpreted as in- 

 dicating the action of selection ; only the selection would have 

 done its work in the past history of the species, instead of acting 

 now, as on the original assumption. In other words, breadth 

 of carapace (or some character correlated with it) had a selection 

 value in the phylogeny ; now this character appears at a late 

 stage in the ontogeny. It is for Prof. Weldon to decide, by 

 further observation, which of these interpretations is to be 

 accepted. R- Meldoi.a. 



A Note on the Tesla Sparkand X-Ray Photography. 



A Crookes' radiometer was supported by its stenr about fotir 

 inches above the hand, which was placcil upon a photographic 

 plate enclosed in two light-light cases. The terminals of a 

 Tesla coil were placed about half an inch from the bulb on either 

 side of it, inclined to one another at an angle of 120°, the vertex 

 of the angle being in the axis of the radiometer. The Tesla 

 discharge was allowed to bombard the bulb for four minutes. 

 On development a clear picture of the bones in the hand 

 appeared. The experiment shows that the X-ray photo can be 

 produced when an exhausted bulb is used having no terminals. 



