LIST OF ILLUSTRATIONS 



FAOB 



In the land of the palms, a California scene Frontispiece 



Five acres of one of the famous new wheats produced at 

 the Minnesota Station, the yield being much above that 

 of the old wheats . . . . . .5 



Microscopic photograph of soil of great fertility . .12 



Microscopic photograph of a soil having no fertility, abso- 

 lutely sterile . . . • . .19 



A striking illustration of soil inoculation. The pots 

 contain clover. The first one, at the left, has not 

 been treated in any way ; the next has no nitrogen ; 

 the next no nitrogen, but inoculated with bacteria; 

 the next no phosphorus ; the next no potassium ; the 

 last has been fed nothing . . . . .31 



Showing length of head of a new wheat. It has been 

 bred not only for size but for disease-resistance and 

 splendid food qualities . . . . .28 



Planting -machine for seeds, so made that absolute accu- 

 racy is secured . . . . . .37 



The group of wheat to the left shows one hundred average 

 heads from a sample bought for experiment. To the 

 right, the same number of heads grown from large 

 kernels from medium heads . . . .44 



To the left, wheat grown from large kernels, small heads; 

 to the right, wheat grown from large kernels from 

 large heads, illustrating selection . . .53 



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