35 



soil. Doubtless this is true of a considerable majority 

 of known soil-living species* Deep-rooted plants are the 



1, 0"n root systems and root habits see: 

 Uobbe,- Landw. Vers. Stat. 4: 217 (1862), 10: 94 (1868), 

 15: 391 (1872), 18: 279 (1875); Fraas,- Wurzelleben der 

 Gulturpflanzen, 1870; Schwarz,- Unters. bot. Inst. 

 (Tubingen 1: 135 (1883); Kraus,- Forsch. Geb. Agr. Physik 

 12: 259 (1889), 15: 234-286 (1892), 17: 35-103 (1894), 

 18: 113-166 (1895), 19j_ 17, 80-129 (1896); King,- Wise. 

 Agr. Exp. Sta., Report 1892 ; 112-120, 1895 . 160-164; 

 Goff,- Wise. Agr. Exp. Sta., Report 1897 ; 286-298; 

 Georgeson and Payne,- Kansas Agr. Exp. Sta., Bull. 75 ; 

 212-222 (1898); Ten Eyck,- North Dakota Agr. Exp. Sta., 

 Bull.36: 333-346 (1899), 43: 535-550 (1900); Busgen,- 

 Allg. Forst.- und Jagd-Ztg. 67: 273-278, 305-309 (1901); 

 Freidenfelt,- Flora 91: 115 (1902); von Seelhorst,- 

 Jour. Landw. 50: 91-104 (1902); Shepperd,- Ilorth Dakota 

 Agr. Exp. Sta., Bull. 64: 525-540 (1904); Booth,- Hew 

 York State Agr. Exp. Sta., Report 1907 . part 3: 345-349 

 (1907); Rotmistrov,- Zhur. Opyt. Agron. 8: 66 7-705 (1907), 

 9_: 1-24 (1908), Root System of Cultivated Plants (1909); 

 Schulze,- Wurzelatlas, vol. 1, (1911), vol. 2, (1914), 

 Festschrift 50 Jubilaum Agr. Chaa. Versuchs u. Kontroll 

 Stat. Breslau, pp. 67-95 (1913); Cannon,- Carnegie Inst, 

 of Wash., Pub* 131 (1911), Pop. Sci. Mon. 81: 90-99 (1912), 

 Science 57: (1913), Plant World 16: 323-341 (1913). 



