MEDICAGO SATIVA 



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turn, exceeding the length of the keel. The stamens are diadel- 

 phous, nine of them being undiverged with the tenth or uppermost 

 stamen free. The stamens forming the staminal tube are held in a 

 state of tension by two projections of the keel which meet in front 



Fig. 155. Root systems of alfalfa in July of second year of growth : A, grown in dry land; 

 B, in irrigated soil. (From Weaver, Root Development of Field Crops, McGraw-Hill Book Co.) 



