LEGUMES AND INOCULATION 



173 



NOTE TO THE TEACHER. Much time can here be given to a study 

 of the tubercles on different plants. Assign drawings from nature of 

 the tubercles on several legumes, as on garden pea, clover, and on any 

 others that may be available. Write to your state Experiment Station 

 and to the United States Department of Agriculture at Washington 

 for any bulletins on soil-improving plants ; also ask that the library of 

 your school be put on their permanent mailing lists, so that the school 

 may receive their future publications. 



FIG. 115. NODULES ON WINTER OR HAIRY VETCH 



