April 22, 1922] 



NATURE 



513 



Our Bookshelf. 



Capita Zoologica. Verhandelingen op Systematisch- 

 j^_^ Zoologisch Gebied. Onder Redactie van Prof. Dr. 

 ^^^^E. D. Van Oort. Deel I, Aflevering i, Nouvelles 

 ^^^^Recherches sur les Nematodes litres terricoles de la 

 ^^tUoUande. Par Dr. J. G. De Man. Pp. 62 + 14 

 ^^vplates. 10 guilders. Deel I, Aflevering 2, Studien 

 ^^m fiber Rhizostomeen mit Besonderer Beriicksichtigung 

 ^^P der Fauna des Malaiischen Archipels nebst einer 

 ^"^ Revision des Systems. Von Dr. Gustav Stiasny. 

 Pp. viii + 176 + 5 plates, ('s Gravenhage: Martinus 

 Nijhoff, 1921.) 16 guilders. 

 In these days of drastic economy it is becoming ever 

 more difficult to find means for the publication of 

 scientific work, especially when it has little or no 

 direct bearing upon utilitarian problems. The system- 

 atic zoologist in particular has to content himself as a 

 rule with as little as possible in the way of paper, 

 letterpress, and illustrations, and it will probably be 

 a long time before we see again in this country a series 

 of zoological monographs comparable with that which 

 embodies the results of the Challenger Expedition. 

 Other countries, however, appear to be somewhat less 

 embarrassed as to ways and means, and we are glad to 

 welcome the appearance of a new Dutch periodical 

 entitled Capita Zoologica, under the editorship of Prof. 

 Dr. E. D. van Oort, Director of the State Museum of 

 Natural History at Leiden. This publication will 

 consist of a series of large quarto memoirs on systematic 

 zoology, which will be issued separately as complete 

 works as occasion requires. The first two are already 

 published, dealing respectively with the free-living 

 Terricolous Nematodes of Holland, by Dr. J. G. De 

 Man, and with the Rhizostomatous Medusae, by Dr. 

 Gustav Stiasny. Both memoirs are fairly copiously, 

 though by no means extravagantly, illustrated, and 

 they form solid and valuable contributions to our 

 knowledge of the groups with which they deal. 



A. D. 



Benzol : Its Recovery, Rectification, and Uses. By S. E. 



Whitehead. With an Introductory Note by the 



Rt. Hon. Lord Moulton. (The Gas World 



Series.) Pp. xiv + 209. (London: Benn Brothers, 



Ltd., 1920.) Price 12s. 6d. net. 



During the war the gas industry received a great 



impetus from the increasing demand for benzol and 



toluol for military requirements, and methods of 



recovery and production were adopted on a scale which 



was little appreciated at the time. One result of this 



was to pave the way for the foundation of a far greater 



benzol industry in this country than was previously 



existent, and the present volume has been written as a 



guide to the principles and practices engendered. 



The text is most thorough, and while essentially 

 practical, it does not ignore theoretical criteria cognate 

 to the technicalities of the subject. The book is built 

 up of exhaustive discussions of the recovery of benzol 

 from gas, its rectification, and the uses to which it and 

 the derivative products may be put. Probably the 

 most interesting sections are those dealing with dyes, 

 explosives, and the use of benzol as a motor fuel, which, 

 although in the former connections modestly regarded 

 by the author as summaries, are none the less useful 



NO. 2738, VOL. 109] 



and comprehensive. It is obviously important that, 

 in view of this country's dependence on foreign resources 

 of petroleum as a motor fuel, every effort should be 

 made to ease the position by the establishment of a vast 

 benzol industry, and in this effort the utmost encourage- 

 ment should be given to those engaged in coal-gas pro- 

 duction ; the present volume is a valuable contribution 

 to this end, and both for educational and technical 

 purposes merits a wide circulation. H. B. Milner. 



The Analysis of Mind. By Bertrand Russell. (Library 

 of Philosophy.) Pp. 310. (London : George Allen 

 and Unwin, Ltd. ; New York : The Macmillan 

 Company, 1921.) 165. net. 

 The title of Mr. Russell's book may raise expectations 

 that it is an exposition or development of his philo- 

 sophical theory. It cannot, however, take rank with 

 his great works. It is a course of lectures, to all 

 appearance a verbatim report, which has been subjected 

 to the very minimum of revision. It is brimming over 

 with casual witty remarks which pass well with an 

 audience, but will not bear reflection. The lectures 

 show Mr, Russell under the influence of two com- 

 paratively recent popular movements in philosophy 

 and psychology, both of which seem to have attracted 

 him powerfully, and neither to have convinced him 

 completely, namely, William James's Neutral Monism 

 and Prof. J. B. Watson's Behaviourism. One lecture 

 deals at some length with the question, " Does Con- 

 sciousness exist ? " The answer reminds one of the 

 famous pronouncement that Shakespeare's plays were 

 not written by Shakespeare but by some one else of the 

 same name. It is easy enough to argue that conscious- 

 ness does not exist, but then there is something we are 

 talking about when we affirm its non-existence, and 

 it is difficult to find any other name for it. In regard 

 to Behaviourism Mr. Russell thinks it a beautiful theory 

 and an ideal method, but then — there are images, and 

 the theory cannot account for them. 



(i) Aspects of Plant Life, with Special Reference to the 

 British Flora. By R. L. Praeger. (Nature Lover's 

 Series.) Pp.208. (London : S.P.C.K. ; New York : 

 The Macmillan Company, 1921.) 6s. net. 

 (2) Mountain and Moorland. By Prof. J. A. Thomson. 

 (Nature Lover's Series.) Pp. 176. (London : 

 S.P.C.K., 1921.) 6s. net. 

 There are many educated persons who are conscious 

 that they miss much of the beauty and interest of the 

 world around them through lack of knowledge and of 

 the seeing eye that knowledge alone can give. To all 

 such these two small volumes published by the S.P.C.K. 

 will prove most acceptable. In an easy and non- 

 technical fashion (i) Prof. Praeger sets forth the condi- 

 tions under which various types of flowering plants 

 exist, the problems by which they are confronted, and 

 the devices by which they triumph. He brings forcibly 

 to mind the deep philosophical nature of the questions 

 that may be raised by the occurrence on hill or in 

 valley of even the humblest plant. 



(2) Prof. Arthur Thomson's book is a delightful com- 

 panion for any one who wishes to enjoy intelligently 

 a holiday among our moors and mountains. It touches 

 in a stimulating and suggestive way on almost every 

 branch of natural history in these favourite districts, 

 and opens out numerous fields of research for the reader. 



S 2 



