160 THE PLANT WOKLD 



Practical Text-Book of Plant Physiology. By Daniel Trembly Mac- 

 Dougal, Ph. D. Octavo, 338 pages, 159 illustrations. Longmans, 

 Green & Co. New Tork, 1901. 



Numerous text-books on general botany have latelj^ appeared, but 

 works devoted to physiology alone have not been so plentiful. In re- 

 gard to the scope of this work, we may quote from the preface: " The 

 chief purpose of the author is to present practical directions for the 

 demonstration of the principal phenomena of the physiology of the 

 plant and also details of experimental methods suitable for exact analy- 

 sis and requisite in research work." The phases of physiological bot- 

 any which have been attracting the greatest attention recently, such as 

 the relation of plants to various stimuli, is given considerable space, 

 the first seven chapters being devoted largelj^ to the different phenom- 

 ena of irritability. The second part of the book is devoted to a more 

 general treatment of the various activities of the plant. In the prepa- 

 ration of chapters relating to special subjects, the author has had the 

 assistance of specialists in those i:)articular subjects, for which due 

 credit is given in the preface. 



As a text-book for use by instructors and teachers of physiologi- 

 cal botanj^ as well as for the laboratory student and investigator, the 

 work will no doubt be found very helpful. The discussions of the vari- 

 ous subjects are necessarily brief, and much attention is given to sug- 

 gestions for experimental work. Citations of literature are frequent. 

 For a fuller treatment of the subjects, the student should have at hand 

 Pfeffer's excellent work, of which a translation recently appeared. 



A very useful portion of the work, and one which will be appreci- 

 ated by the instructor as well as the laboratory worker, is the appen- 

 dix, which includes tables for the conversion of British into metric 

 linear measures, also for the conversion of metric weights and measures 

 to United States weights and measures, comparison of Fahrenheit and 

 centigrade scales, besides the density of different substances at different 

 temperatures, etc.; also some formulae and a table of osmotic values, 

 the latter taken from Pfeffer's work. — C. L. S. 



