LIST OF ILLUSTRATIONS xxvii 



60. Apparatus for cleaning and grading seed grain by the spe- 



cific gravity method 182 



61. Pot experiment with Manchuria barley, showing the effect 



of selecting large seed (Derr) 185 



62. Cereal nursery at the Minnesota Agricultural Experiment 



Station (Harlan) 197 



63. Spike of Fultz wheat (Leighty) . . . . . .200 



64. Hybridizing barley (Harlan) 216 



65. Cereal nursery cage (Derr) 217 



66. Spikes of Fulcaster wheat (Leighty) 220 



67. U. S. C. I. wheat hybrid, Ghirka Winter x 1392 . . .223 



68. U. S. C. I. wheat hybrid, Banat x 1409 . . . .224 



69. U. S. C. I. wheat hybrid, Jones Winter Fife x Ufa Emmer. 225 



70. U. S. C. I. wheat hybrid, Theiss x Ufa Emmer . . . 226 



71. U. S. C. I. barley hybrid, Arlington Awnless (Derr) . . 227 

 72 Spike and spikelet of a hooded barley 228 



73. Map of European Russia, showing extent and divisions of 



the Chernozem (Stevenson) 238 



74. Map of the United States and Canada, showing the Great 



Plains Area (Stevenson) 241 



75. Climatological map of European Russia (Stevenson) . . 257 



76. Climatological map of the United States and Canada . . 258 



77. Climatological map of Argentina (Stevenson) . . . 264 



78. Chart, showing the period between seeding and harvesting 



spring oats in the states east of the Rocky Mountains . 272 



79. Chart, showing the period between seeding and harvesting 



winter wheat in states east of the Rocky Mountains . 273 



80. Map of the world, showing distribution of wheat . . . 279 



81. Map, showing distribution of wheat in European Russia . 281 



82. Map, showing distribution of wheat in the United States 



and Canada ......... 282 



83. Map, showing distribution of wheat in Argentina . . 284 



84. Milling district in Budapest 285 



85. Soil exchange plats of Crimean (Turkey) wheat in environ- 



mental experiments ....... 294 



86. Erosion of soil in Maryland (Derr) 305 



87. Terrace or contour-farming at the Tennessee Agricultural 



Experiment Station (Derr) 306 



88. A lime-spreader, upper view (U. S. Dept. Agr.) . . .309 



