



The 



Plant World 



Mr Itllll 1^^111 1 vl 











j\ Magazine of General Botany 







VOLUME 13 







NUMBER 3 







MAR. 190 9 







Containing 







Roles of the Soil in Limiting Plant Activities 



By B. E. Livingston 49 



Bogs, Their Nature and Orgin (concluded 



By J. \V. Harshberger 53 



A Witch's Broom of the Desert 



By P. C. Standley 61 



Vegetation and Altitude 



By C. H. Shaw 63 



Perennial Dodder 



By F. E. Lloyd 65 

 A Repeated Cycle in Assimilation 



By B. E. Livingston 66 



Books and Current Literature 67 

 Notes and Comment 71 







Tucson, Arizona 







Entered as Second Class Matter, Dec 17, 1907 , at the Post-0 jfice, Tucson, 

 Arizona, under the Act of Congress of March 3, 1879 



