THE PLANT WORLD 219 



the world on the lookout for new plants that may be grown successfully 

 in this country, or in securing better and stronger strains of well- 

 known plants. The introduction of a hard-grained rice from Japan, of 

 drought and fungus resisting wheat from Russia, of salt-bushes from 

 Australia, and date palms from the Orient, are a few of the numeroiii^ 

 examples that may be cited. 



BOOK REVIEWS. 



Statistical methods with special Reference to Biological VARiATioisi. 

 By C. B. Davenport, Assistant Professor of Zoologj^ University of 

 Chicago. 16mo. Morocco flexible covers, 148 pp. Protractor and 

 20 pp. coordinate paper. Price $1.25. John Willey & Sons, New 

 York. 



The stud}' of biological variation has received much attention ever 

 since Darwin first called the attention of the scientific world to its great 

 importance as a factor in the evolution of living forms, but strange as it 

 may appear, it is only recenth^ that the subject of variation has re- 

 ceived systematic and accurate study. The most work along this line 

 has been done by the zoologists, but it is time botanists began to realize 

 more fully the great importance of this work, and to devote more atten- 

 tion to it. 



The little book before us is devoted to methods of making quanti- 

 tative studies of species and of organic variation in general, and the 

 plotting of the results of such study. The subjects of the first five 

 chapters are as follows: Chapter I. On the Methods of Measuring Or- 

 ganisms. II. On the Seriation and Plotting of Data and the Norma] 

 Frequency Polygon. III. Abnormal Frequency Polygons. IV. Cor- 



