XXX LIST OF ILLUSTRATIONS 



FIGURE PAGE 



146. Cutting milkweed out of oats (U. S. Dept. Agr.) . . 467 



147. Weed-spraying outfit in North Dakota (Derr) . . .469 



148. Adult male of the Hessian fly (U. S. Dept. Agr.) . . 472 



149. Pupa or "flaxseed " of the Hessian fly (U. S. Dept. Agr.) . 473 



150. Stages or instars in the life-history of the chinch bug (U. S. 



Dept. Agr.) 478 



151. Wingless female of the spring grain louse (U. S. Dept. Agr. ) 481 



152. Seedling wheat plant infested with the spring grain louse 



(U. S. Dept. Agr.) 482 



153. Winged adult of the spring grain louse (U. S. Dept. Agr.) 483 



154. Granary weevil, showing different stages ; also the mature 



rice weevil (U. S. Dept. Agr.) . . . . .490 



155. Angoumois grain moth (U. S. Dept. Agr.). . . . 495 



156. Mediterranean flour moth (U. S. Dept. Agr.) . . .497 



157. Resistance of Durum wheat to rust, compared with com- 



mon wheat (E. G. Johnson) ..... 512 



158. Minn. No. 188 wheat affected with bunt (E. G. Johnson) . 514 



159. Covered and loose smut of oats (E. C. Johnson) . . . 516 



160. Covered smut of barley (E. C. Johnson) . . . .618 



161. Smut-cleaning machine (E. C. Johnson) .... 520 



162. Simple farm device for smut treatment (E. C. Johnson) . 522 



163. Increase of barley smut in two years without seed treat- 



ment (U. S. Dept. Agr.) ...... 524 



164. Pride of Genesee wheat affected with loose smut (E. C. 



Johnson) 526 



165. Loose smut of barley (E. C. Johnson) . . . .528 



166. Artificial infection of oat seedlings with the scab fungus 



(E. C. Johnson) 531 



167. Ergot on rye (Derr) 534 



168. Ergot on barley (Derr) 535 



169. Diagram showing a simplified plan of a modern mill (Sperry 



Milling Company) 550 



170. Variation in the size and shape of the scutellum in different 



barleys (drawn by Boettcher, from Photograph by 

 Harlan) 561 



171. Cooperative grain warehouse at Yuba City, Cal. (Blanch- 



ard) \ 565 



172. Grain elevator at Portland, Me. . . . . . .567 



173. Interior of grain elevator at Portland, Me 568 



