HOW PLANTS ARE IMPROVED 113 



For a long time plant breeders worked in a " hit-and- 

 miss " fashion, but now they are guided in their work 

 by certain laws, particularly by the laws of Mendel. 

 These are explained in two books, one by Professor 

 Bailey, and one by Professor de Vries, each of which 

 has the same title, " Plant-breeding. " 



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