CONTENTS. 



Page. 



Introduction 7 



ii \ ironment experiments 7 



Conduct of the experiment* 9 



Variations in nitrogen content 13 



t of acclimation 14 



Influence of heredity 15 



Slight influence of the soil 16 



Variations in physical appearance 16 



K lation between absolute weight and percentage of protein in the grain 17 



Influence of local weather conditions 18 



18 



[Hull 



(5) 



