Acclimatization in Arizona. 23 



showers of 1909, which collected on the University grounds in 

 swales where the soil is naturally heavy, healthy, rapid-growing 

 plants of Eucalyptus polyanthema became badly chlorotic and 

 some of them died. On the other hand, the writer has observed 

 very healthy specimens of Eucalyptus rudis, which species is 

 most susceptible to chlorosis, growing in very sandy soil along 

 irrigation ditches within six feet of the water's edge. As op- 

 posed to the above there are other species like Brodiaea and 

 Calochortns, native liliaceous plants, that will not grow success- 

 fully from year to year in moderately sandy soil, requiring on 

 the other hand, the heaviest clav. 

 Arizona Experiment Station, 

 Tucson, Arizona. 



BOOKS AND CURRENT LITERATURE. 



The Chemistry of Plants. — ^That the study of plants must 

 become ever more and more chemical in its nature is obvious 

 when one considers that all the plant forms and structures (the 

 mere description and classification of which has mainly occupied 

 botanists to the present time) are the results and tangible evi- 

 dences of chemical and physico-chemical processes taking place 

 within the organism. Plant morphology must be regarded as 

 a description of the end results of these internal physiological 

 processes, and there can be no doubt that the relationships of 

 structures will receive much light from deeper inquiries into the 

 physical and chemical reactions by which the latter come into 

 being. The present tendency of all lines of botanical study is 

 to become physiological, and of plant physiology to become more 

 and more a search for the fundamental causes of plant phe- 

 nomena, emphasizes the importance of plant chemistrv and 

 plant physics. Every student of plants who hungers for a 

 knowledge of causes, believing with Cicero that felix rui potiiit 

 rerum cognoscere causas, and who has an eve not only to this 

 "happiness" arising from a knowledge of "the causes of things," 

 but also to the future development of botany, will be glad of 

 the appearance of the second and last volume of Euler's new 



