BOOKS AND WRITERS 



"A Textbook of Grasses"" is the title of a new book by A. 

 S. Hitchcock, Agrostologist of the United States Department 

 of Agriculture, in which the author has endeavored to include 

 everything of value on the subject of our wild and cultivated " 

 forage crops. One will look in vain for a systematic descrip- 

 tion of grasses in this book. Onh^ those are mentioned which 

 possess some degree of usefulness as food for man or stock. 

 The book, however, is much more than a discussion of grasses 

 as botanical species. There are chapters dcA^oted to pastures, 

 meadows, lawns, hay, weeds, ornamental grasses and grasses 

 for purposes other than food. The morphology of the vegeta- 

 tive and floral organs is discussed in two chapters, while 

 ecology, taxonomy and classification have chapters alloted to 

 each. The A^arious grass genera are systematically treated and 

 keys to the important species given. The book is of impor- 

 tance for containing a large amount of matter relating to 

 grasses that is usuall}^ missing from such books. The volume 

 covers 260 pages with upwards of sixty illustrations. It is 

 published by the iVlacmillan Company, Xew York, at $1.50 

 net. 



The mechanism of the ascent of sap in stems has never 

 received an adequate explanation. The force necessary to 

 raise the sap to the tops of high trees is considerable, often 

 amounting to a pressure equal to twenty atmospheres, and 

 such plant processes as have heretofore been brought forward 

 to account for it have had to be dismissed, one after another, 

 as unequal to the task. In these investigations, capillarity, 

 osmosis, evaporation, root pressure, vital activity in the cells, 

 and many others have been tried and found wanting-. An Irish 

 botanist, however, Dr. Henry H. Dixon, of Trinity College, 

 Dublin, seems to have solved the problem. He finds that water 

 has a surprising cohesive power when enclosed in the ducts of 



