127 



are considered in chapter 9. The relationship between animals 

 and plants is termed coaction but chapter 10 is largely a very 

 laudable treatise of the application of ecological principles to 

 conservation. The underground parts of plants are treated at 

 length. Then follow chapters dealing with the aerial environ- 

 ment — humidity, wind, and evaporation; temperature; light. 

 Chapter 15 is a brief discourse on the use of plants themselves 

 (phytometers) in studying the environment. The chapter on 

 adaptation to water gives a basic presentation of ecological 

 plant anatomy. The fact that plants and plant communities are 

 indicators of the condition of the habitat is brought out in 

 chapter 17. The reader will experience little difficulty in men- 

 tally transposing this chapter into plants and communities with 

 which he is familiar. The last chapter introduces the reader to 

 plant geography by briefly describing the climax formations of 

 North America. 



The book is well illustrated throughout by examples, tables, 

 charts, line drawings, and photographs. Many of the topics 

 are accompanied by directions for experimental procedure, as 

 they were in the first edition. A few paragraphs at the first of 

 the book outline a course with field work as the authors them- 

 selves conduct it. There is a bibliography of 1,035 citations for 

 those who desire further work in the subject. 



Water Culture of Plants — Ellis and Swaney^ 



G. 1. Hastings 



Water culture in its various forms has attracted much at- 

 tention in the last few years. Descriptions of culture solutions 

 and methods of growing plants in them have appeared in various 

 leaflets, — here we have a small book that attempts to give com- 

 plete descriptions. The authors describe methods of growing 

 plants in liquid and in sand or cinders irrigated with the solu- 

 tions. The descriptions are evidently based on much experi- 

 mental work done by the authors as well as work done experi- 

 mentally or commercially by others. In addition one chapter 

 is devoted to the effects of plant hormones in stimulating growth 

 and the work of Dr. Blakeslee in developing new forms of double 



2 Soilless Growth of Plants. Carleton Ellis and Miller W. Swaney. 155 

 pages, 55 figures, 3 colored plates. Reinhold Publishing Corp. 1938. $2.75. 



