244 



NATURE 



[July i6, 1908 



in discharging- an insulator is similar to that of points 

 un a conductor. 



The remainder of the book is much better than the 

 portion on electrostatics; but there are several errors, 

 and, as usual, the author tries to cover too much 

 ground. When will authors realise that there is no 

 royal road to learning in science or elsewhere? If 

 those who have special aptitude for these studies re- 

 quire years of work to grasp the fundamentals of elec- 

 tricity, is it likely that the " plain man " will get any 

 good from reading 400 " elementary " pages attempt- 

 ing to deal with the whole subject ? Such publications 

 only increase the number of persons who talk and 

 write about things of which they imagine themselves 

 masters, but are in reality ignorant. 



OUR BOOK SHELF. 



Handbook of Floivcr Poniiiation, based upon Herman 

 MiiUer's Work " The Fertilisation of Floivers by 

 Insects." By Dr. P. Knuth. Translated by Prot. 

 J. R. Ainsvvorth Davis. Vol. ii. Pp. viii-l-703. 

 (O.xford : Clarendon Press, 1908.) Price 31s. 6</. 

 net. 

 .'\s stated in our review of the first volume 

 (vol l.xxiv., 1906, p. 605), Knuth's " Handbook of 

 Flower Pollination " is an encyclopaedic work, and 

 the second volume, which is now before us, dealing 

 as it does with the various methods of pollination in 

 fifty-six families of dicotyledonous plants, is even more 

 directly a book of reference than the first volume, 

 which was of an introductory nature. In this second 

 volume the author deals seriatim with all the genera 

 and species in the natural orders under consideration, 

 describes the structure of the flowers in so far as it 

 affects directly or indirectly the mode of pollination, 

 and cites the various direct observations on pollina- 

 tion made by himself or others. To each species of 

 plant is appended a list of the insects which have 

 been observed visiting the flowers, together with a 

 statement as to whether the insects in question were 

 devouring or collecting pollen or sucking nectar. 



The translator has facilitated the use of the volume, 

 which will be more frequently consulted than read 

 through, by repeating more fully the titles of the 

 books and papers referred to than is the case in the 

 original. Few, if any, of these references are more 

 recent than 1898, the date of publication of vol. ii. 

 in the German edition, though the list of references 

 in the first volume of the translation is brought uj) 

 to 1904. 



No doubt the labour involved in bringing up to 

 date the various recorded visits of insects to flowers 

 would have been very considerable, but on .points of 

 a more general character the translator might have 

 added some additional information in the form of 

 footnotes. Thus in dealing with those Papilionacere 

 which have so far been recognised as self-sterile, the 

 translator might have mentioned the more recent in- 

 vestigations of Kirchner, and might hav-e referred to 

 the illuminating generalisation of that author, who 

 found that while so many perennial Leguminosce are 

 self-sterile, all the self-fertile forms of Papilionaceae 

 are annuals which are dependent for their continued 

 existence on each year's successful crop of seeds, and 

 cannot, therefore, afford to be self-sterile. Similarly, 

 in dealing with the genus .Mchemilla, mention might 

 have been made of the recent investigations of Stras- 

 burger and others on the phenomenon of apogamy 

 so characteristic of a certain section of this genus. 



NO. 2020, VOL. 78] 



A useful improvement is the addition to the transla-- 

 tion of a list of the natural orders dealt with in this- 

 volume, which will be as welcome to English readers 

 as the more general introductory volume has proved 

 itself to be. 



Tlic Theory of Ions: a Consideration of its Place in 

 Biology and Therapeutics. By Dr. W. Tibbies. Pp- 

 ix+131. (London: Rebman, Ltd., 1908.) Price 

 2S. bd. net. 



This is a bright little book written with the object 

 of pointing out the bearings of physical chemistry 

 on physiological processes. Dr. Tibbies, however, 

 like Pauli, from whose book copious quotations are 

 made, is rather inclined to make the phenomena of 

 ionisation and the behaviour of colloids explain too- 

 much. There is no doubt that physical chemistry will ' 

 in the future make clear a good deal of what is at 

 present obscure in bio-chemistry ; but a full apprecia- 

 tion of this effect cannot be gained until two things 

 have occurred ; one of these is a settling of the many 

 vexed points of quite a fundamental nature between 

 the phvsical chemists themselves, and the other is a 

 fuller knowledge of the chemistry of protoplasm in 

 general and of the protein constituents of protoplasm 

 in particular. 



.\t the present day there is probably only one sen- 

 tence in the book with which all will be in agree- 

 ment, and that is, " We are far from a satisfactory 

 insight into the nature of the effect of ions." 



The author gives a fairly accurate account of the 

 advances recently made in physiological chemistry, 

 although it will probably be found too compressed tO' 

 appeal to any but those fully up in the subject. Hi& 

 nomenclature is not uniform, and is therefore con- 

 fusing to the reader; thus he sometimes speaks of 

 proteins, sometimes of proteids ; in some places of 

 amino- and in others of amido-acids ; there are a 

 number of uncorrected press errors, for instance, 

 glycvl-glycyl for glycyl-glycine. The close similarity 

 of the words absorption and adsorption should have 

 rendered him especially careful in proof-correcting, 

 especially where both are mentioned on the same 

 page. He also gives us the rather startling informa- 

 tion that choline is present in bile salts. 



The work does not profess to contain anything 

 original; it is rather a compilation from previous 

 writers strung together with the object of emphasising 

 the importance of a knowledge of solutions in the 

 elucidation of phvsiological, pathological and thera- 

 peutical problems. Dr. Tibbies is not always judicious 

 in his selections or judicial in their valuation. For 

 instance, the old theories of Pfluger, Latham, Loew, 

 and others on the distinction between living and dead 

 proteins are all advanced as though they were still 

 tenable and of equal value with the views of Fischer 

 which depend on actual work and not on mere 

 speculation. 



Still, the book is interesting, and contains many 

 suggestions of importance, but the author has not 

 realised that it is not possible to write a complete 

 text-book of organic chemistry, bio-chemistry, physical 

 chemistry, therapeutics and immunity within the 

 short compass of 130 small pages, or that the ionic 

 theory or any other theory, however new and attrac- 

 tive, is sufficient to explain the universe. 



The Libraries of London : A Guide for Students. Pre- 

 pared by R. .\. Rye. Pp. 90. (London : The 

 University of London, 1908.) Price 6d. net, post 

 free gd. 

 The libraries described in the book, with the excep- 

 tion of those of certain schools of the L"niver>ity, and 



