March 25, 1920] 



NATURE 



97 



a personal preference which has been disappointed 

 by the scantiness of the references in this volume 

 to original sources of information, and to 

 authors ; in our opinion, the more authoritative a 

 book is, the more importance attaches to complete 

 references, whereby the reader is assisted in pur- 

 suing his investigations into any particular ques- 

 tion which interests him. We hold, too, that the 

 mention of authors' names is important for other 

 reasons than the mere gratification of their per- 

 sonal vanity ; it is an aid to memory and to verbal 

 discussion (how otherwise — to take examples at 

 random — shall u-e attain to the definiteness of 

 meaning which we associate with "Lenz's law," 

 the "Rankine cycle," "Bernoulli's equation," or 

 the "Willan's line"?); and it is of enormous 

 assistance to the reader in helping him to fit each 

 new fact or theory into his mental picture of the 

 scientific structure. We might add that con- 

 sistency demands either the suppression of all 

 references to individuals (which is no longer think- 

 able) or the adoption of the course which we 

 advocate : no one would accuse Mr. Bairstow of 

 partiality (and if a refutation of the charge were 

 wanted, it could be found in the entire absence 

 of all reference to his own part in the work which 

 he describes), yet we have been struck )yj the 

 apparent arbitrariness with which authors' names 

 have been included or suppressed. We are 

 : conscious that it would be very difficult to 

 ig-ive complete references at the present time, 

 mainly because of the unfortunate preference for 

 'anonymous reports which was so prevalent in 

 I the early days of the war; but this difficulty should 

 'be removed by the publication of the reports in 

 their final form, and we shall hope then to see 

 those additions which will make this book the 

 standard work of reference in its subject. 



The printing and paper of the book are good, 

 and a special word of praise is due to the illus- 

 trative diagrams, which appear to have been 

 re-drawn specially for this work. The book is 

 thick and rather heavy, and those who will make 

 it a work for daily reference will probably find it 

 desirable to clothe it in rather stronger binding. 



Gymnospermic History. 



Fossil Plants: A Text-book for Students of 

 Botany and Geology. By Prof. A. C. Seward. 

 Vol. iv. : Ginkgoales, Coniferales, Gnetales. 

 (Cambridge Biological Series.) Pp. xvi-i-543. 

 (Cambridge : At the University Press, 1919.) 

 Price I guinea net. 



TO every science, works which bring together ! 

 the data of the subject are essential, and to | 

 none more so than to palaeobotany, which is based I 

 NO. 2630, VOL. 105] 



on the correlation of fragmentary remains from 

 all countries and of all ages. Prof. Seward has 

 served his science well in completing the almost 

 Herculean task of writing a text-book covering 

 the whole field of these plant remains. The first 

 volume appeared many years ago, and this, the 

 fourth, is the final one of the series. 



This disappointingly closes with the higher Gym- 

 nosperms, the series of plant families treated, and 

 the author does not propose to continue the work 

 so as to deal with the flowering plants. This is 

 perhaps scarcely surprising, as the data bearing 

 on the flowering plants are very complex and of 

 a fragmentary and unsatisfactory nature, and 

 have, moreover, been little studied in this country. 

 Some up-to-date handling of the Angiosperms is 

 greatly to be desi'-ed, and students will await with 

 some impatience the appearance of the independent 

 work Prof. Seward promises, in which he proposes 

 to deal with the generalities of plant distribution, 

 taking the fossil Angiosperms into account. 



Prof. Seward's text-book should be a useful 

 tool, not only to palaeobotanists in particular, but 

 also to all students of either botany or geology in 

 general. Somewhat lost sight of in the mass of 

 fossil species, there are, prefacing each group, 

 excellent accounts of the living representatives of 

 each family. 



In a volume of such laborious detail as the 

 present one, which appeals to the specialist rather 

 than to the average layman, there must, of course, 

 be many comparative trifles which tend to side- 

 track any critic by inducing an attempt to deal with 

 minor controversial matter. To do this, however, 

 in a general review would be both ungenerous 

 and unfair, because the amount of public recogni- 

 tion and the gratitude which scientific authors 

 receive is small and out of proportion to the 

 labour and to the sacrifice involved in their tasks. 



Misprints are remarkably few, and the general 

 perspective of presentation is well preserved, 

 although here and there the author has naturally 

 indulged in rather longer descriptions of one or 

 two individual species which are first published in 

 this book than such specimens would be allowed 

 had they been published separately at an earlier 

 date. It is doubtful, as a matter of general policy, 

 whether a text-book is the place to publish new 

 species at all, although any research worker must 

 have in his notes records of small and relatively 

 unimportant species which scarcely deserve inde- 

 pendent memoirs, and the temptation to put them 

 in the text-book must be very great. 



Knowledge of the higher Gymnosperms largely 

 depends on petrified material of secondary timber, 

 for although fragments of foliage impressions 

 with a few cones are known, they are compara- 



