ON THE SMALL GRAINS 



few varieties in the field grains and so many in 

 corn and singly cultivated garden vegetables, in 

 which variation is quite evident and varieties are 

 easily segregated. 



It is obviously necessary that a plant grown 

 from the seed, and for its seed, must reproduce 

 itself accurately from generation to generation; 

 otherwise the agriculturist could have no assur- 

 ance as to what might come forth when he sows 

 his grain. 



In point of fact, the numerous varieties have 

 become fixed so that each may be sown with a 

 large measure of assurance that the crop will have 

 the uniform character of the seed. The differ- 

 ences among the different varieties have to do with 

 size of grain, productivity, season, of ripening, pro- 

 tein content, quality of so-called hardness, which 

 is important in bread-making, color of grain, pe- 

 culiarities as to beards, chaff, and the like; and — 

 perhaps most notable of all — condition of suscepti- 

 bility or immunity to the attacks of the fungus 

 known as rust, which is the chief enemy of the 

 wheat, and a perpetual menace to the crop. 

 A Microscopic Pest 



There are always penalties associated with any 

 specialized development in a cultivated plant or a 

 domesticated animal. 



In the case of the small grains, the penalty of 



[47] 



