362 
Reviews. 
REVIEWS 
AN INTRODUCTION TO THE CHEMISTRY OF PLANT 
PRODUCTS: 
By P. Haas and T. G. Hill. London (Longmans, Green & Co.), 
1913; pp. xii and 401. Price 7s. 6d. Net. 
HILE it is generally admitted that a sound knowledge of 
chemistry and its experimental technique is an essential 
part in the equipment of the botanist, up to the present time there 
has not been available for English readers any single book pre¬ 
senting in a direct and readable manner the main facts in 
biochemistry of plants. This lack the authors of the work under 
review have successfully attempted to supply, inasmuch as they 
have brought together within the limits of a handy volume an 
extremely clear account, easily assimilable by botanical readers 
with even a relatively slight amount of chemical training, of the 
more important organic compounds occurring in plants, and of their 
physiological significance. The authors are to be congratulated on 
the happy result of their collaboration, for the dovetailing of the 
chemical and botanical sections throughout the book has been 
skilfully done, and these sections include much of the most recent 
work on such subjects as colloids and enzymes, as well as most of 
the recent important advances in the physiology of vegetable 
metabolism. 
The book is divided into nine parts, dealing with (i) fats, 
oils, waxes, phosphatides; (ii) carbohydrates; (iii) glucosides; 
(iv) tannins; (v) pigments; (vi) nitrogen bases; (vii) colloids; 
(viii) proteins; (ix) enzymes. Under each heading the authors 
give a concise account of the distribution and occurrence of these 
substances in plants, their chemical and physical properties, 
methods of extraction, chemical and microchemical reactions, and 
significance in metabolism. The descriptions are not overloaded 
with references to literature, though the main sources of further 
information are indicated, and the material presented has been 
carefully and judiciously selected, much of the older literature 
dealing so largely with impure products having been wisely ignored. 
Doubtless owing to their anxiety to avoid the inclusion of state¬ 
ments based on quite recent work which may or may not be confirmed 
by future investigation, the authors have dealt with hardly any 
work published since 1910; for instance, the work of Sergius 
Ivanow on the metabolism of fats in higher plants, published in 
1911 and 1912, is not mentioned in the book, though on p. 43, 
under the heading “ Further References,” a citation is given of his 
1912 paper dealing with the synthesis of fats in the ripening 
of oily seeds. However, the authors have accomplished very 
successfully their difficult task of discriminating well established 
facts from statements requiring confirmation, and they have pro¬ 
vided exactly what is required by the botanical reader—a direct 
and simple statement of the main facts concerning the nature and 
relationships of the various compounds built up and broken down 
in the course of metabolism in plants. The book ought to be used 
