598 



NATURE 



[October 20, 1904 



Unfortunately for this argument, however, alcohol 

 (ethyl) is itself a biochemical product. 



The fifth chapter deals with the modes of preparation 

 and extraction of odorous compounds, and with their 

 synthetical production. The special part of the work 

 (pp. 67-175), devoted to the description of the general 

 modes of preparation of the various compounds 

 classified under chemical families, may be looked upon 

 as a chapter of synthetical organic chemistry having 

 special reference to the formation of odorous com- 

 pounds, and requires no further comment. 



The headings of chapter vi. (physical properties of 

 odorous compounds), chapter vii. (chemical characters 

 and relations between odour and chemical constitution), 

 chapter viii. (quantitative valuation), chapter ix. 

 (physiological relations), and chapter x. (applications 

 of odorous compounds) sufficiently indicate their con- 

 tents. Chapters vii. and ix. will be found of interest 

 to physiologists as well as to chemists. 



We have not found many slips in this little mono- 

 graph, and it can be safely consulted by all who are 

 interested in the subject. The statement (p. 184) that 

 »n-oxybenzaldehyde derivatives do not occur in nature 

 is erroneous (see, per contra, Jowett, Trans. Chemical 

 Society, vol. Ixxvii. p. 707). Haller's important partial 

 synthesis of camphor from homocamphoric acid (p. 145) 

 might have been mentioned in the reference given in 

 che foot-note. The omission of English firms from the 

 list on pp. 20-21, and the faulty arrangement of the 

 tables on pp. 38-57, have already been referred to. 



Those chemists who, without any special knowledge 

 of the subject, will take the trouble to look through this 

 volume cannot but realise that a new and important 

 branch of industry has been developed out of the 

 ancient art of perfume making. It is apparent also 

 that this newer development is the direct outcome of 

 the application of chemical science — the utilisation for 

 practical purposes of facts and principles discovered by 

 laboratory research. It is the history of the coal-tar 

 colour industry re-told, and we may fairly ask, as in 

 the case of this last branch of manufacture, what is 

 this country doing in the matter? The writer does not 

 propose to do more than raise the question here, be- 

 cause the set reply of " imperfection of patent laws " 

 and " want of duty-free spirit " will no doubt be con- 

 sidered all-sufficient by the majority of our manu- 

 facturers. Passing over this point, however, there is 

 another aspect of the modern perfume industry which 

 is of particular interest. Concurrently with the de- 

 velopment of synthetical processes and the introduction 

 of new products, a keen and searching examination 

 of volatile plant oils has for many years past been 

 systematically carried out in the laboratories of several 

 foreign factories. Without wishing to be invidious, 

 the firm of Schimmel and Co., of Leipzig, may fairly 

 be named as pioneers in this branch of work. The 

 semi-annual report of this firm is a perfect mine of 

 information concerning the chemical composition of 

 ethereal oils. Now the detection of the chemical con- 

 stituents of products resulting from the vital activity 

 of plants is also a matter of physiological importance, 

 so that the workers in this field — prompted, no doubt, 

 primarily by practical considerations — are accumulating 

 NO. 1825. VOL. 70] 



a stock of material for which plant physiologists ought 

 to be grateful. Certainly no physiologist can afford 

 to ignore this material, buried though it may be in a 

 trade publication, and worked up without direct scien- 

 tific aim. But the methods employed and the results 

 achieved are as purely scientific and far more definite 

 than much of the work that at the present time passes 

 into literature as physiological chemistry. We have 

 as pretty an illustration as modern times can furnish 

 of the action of pure science upon industry, and the 

 reaction of industry upon pure science. 



R. Meldola. 



SYSTEMATIC BOTANY. 

 The Classification of Flowering Plants. Vol. i. 

 Gymnosperms and Monocotyledons. By A. B. 

 Rendle, D.Sc. Pp. xiv + 403. (Cambridge: Uni- 

 versity Press, 1904.) Price los. 6d. net. 



THE practice which is gaining ground, whereby, to- 

 the exclusion of the general text-book, the 

 specialist produces a book in which he takes up merely 

 his own branch of a scientific subject, is satisfactory 

 both from the point of view of the author and the reader. 

 The author is well qualified to express his opinions, 

 and the reader cannot fail to learn much from the 

 critical exposition which he is tolerably sure to obtain. 

 The book under notice is significant not only because 

 it is written by one of our leading systematists, but 

 also inasmuch as it is one of the first taxonomic 

 treatises — another is Willis's " Manual of Flowering 

 Plants and Ferns " — which follows Engler's system 

 of classification. Bentham and Hooker's classification is 

 followed in most British herbaria and collections, but 

 there is much to be said in favour of training students 

 in the system which, originally propounded by Eichler, 

 has been modified by Dr. Engler, one of the principal 

 reasons being that the arrangement of orders, although 

 not developmental, at any rate provides a sequence 

 which is distinctly helpful. 



Regarding the title, whereas it is now recognised 

 that the spore-bearing shoots of some of the Pteri- 

 dophyta may be called flowers. Dr. Rendle has used 

 the term in its ordinary signification, and the first 

 volume deals with Gymnosperms and Monocotyledons, 

 while a second volume will be devoted to Dicotyledons. 

 After a short historical review of the principal 

 systems of classification which have been proposed, the 

 author takes up the Gymnosperms, making six classes 

 by the inclusion of the two fossil groups, the 

 Cordaitales and the Benettitales. A chapter upon the 

 morphology of the Angiosperms follows, after which 

 the remainder of the book is concerned with the classi- 

 fication of the Monocotyledons. 



The Gymnosperms have been very much to the fore 

 of late years, and there is nothing strikingly new in 

 the treatment of the group. The interweaving of the 

 fossil classes is distinctly rational, and the reader will 

 find a good general account, including the results of 

 modern research. A considerable number of the dis- 

 tinctive features of the genera appear in the general 

 account, and a few in the enumeration of the genera, 

 but the latter might with advantage have been 

 expanded. 



