92 PRACTICAL PHYSIOLOGY OF PLANTS. 



tackle more than one of these enormous groups, and it would have 

 been better to treat them separately from the mere consideration of 

 convenience. However, this is the beginning of a great under- 

 taking ; it would be easy to find faults ; we do better to wish it all 

 success, and we hope to give from time to time notices of its 

 progress. The plates, if somewhat diagrammatic, are a very usjful 

 part of the work, and the book will have a value to students of 

 Botany, far fi-om Nebraska, on general botanical grounds. 



G. M. 



Practical Physiology of Plants. By F. Darwin, M.A., F.R.S., and 

 E. H. Acton, M.A. Cambridge : University Press. 1894. 

 8vo, pp. xviii, 321, with 43 illustrations in the text. Price 6s. 



This is the second volume in the Biological Series of the Cam- 

 bridge Natural Science Manuals which Mr. Shipley is editing, and 

 the first botanical work. Like several other practical manuals, it 

 originated in the written instructions necessary to a class of students 

 actually carrying out the experiments, and should therefore be free 

 from the faults and pitfalls characteristic of a mere compilation. 

 In the first instance, however, the directions were materially sup- 

 plemented l)y the presence and help of the teacher and author, and 

 if their extension and elaboration in the little book before us is to 

 prove useful to a wider circle of students, the mediation of an 

 efficient teacher will be indispensable. Such a one will find the 

 diiections sufficient, and as a large number of the experiments 

 require only simple apparatus, the work will be welcomed in colleges 

 and schools where modern methods are in vogue. 



There are two parts — Part i., on General Physiology, essentially 

 botanical; Part ii., on Chemistry of Metabolism, essentially chemical. 

 The first, occupying two-thirds of the whole, is divided into eiglit 

 chapters, and deals with processes of respiration, assimilation, 

 including production and reactions of chlorophyll, further stages of 

 nutrition, transpiration, the physical and mechanical properties 

 involved in osmosis, turgor, tissue-tensions, &c., the phenomena 

 associated with growth, and the various movements of adult 

 members, whether spontaneous or in response to special stimuli. 

 The second part, chapters 9-17, is a classified guide to the pre- 

 paration and separation, and the qualitative or quantitative exami- 

 nation, of the numerous and varied substances occurring in the 

 plant-tissues, a knowledge of which is essential to a proper under- 

 standing of the constructive and destructive processes involved 

 in the life of a plant. It affords material for an interesting course 

 in a chemical laboratory. 



As already hinted, the book is not one to put into the hands of 

 the unaided student, and there are instances where the more 

 advanced worker would welcome a little more information. For 

 instance, on p. 35, under the heading, "Evolution of Oxygen," 

 following several experiments by which the evolution of oxygen 

 from living plants can be demonstrated, we find reference to 

 Deh^rain's method. A current of air is drawn through a glass 



