T 



TESTING CTTLTURES OE NODULE-FORMING BACTERIA. 



ton wool. The leguiniiious plants grow Avell, and if the cnltnre used 

 for inoculating- is in proper condition normal nodules are soon formed. 

 By this procedure it has been possible to distinguish shar])ly be- 

 tween the inoculating power of ai^parently identical strains of bac- 



Fio. 1. — Jars for testing the inoculating power of different strains of Bdciiliis niiVivivola. 

 In tlie jar at the right are inoculated garden-pea plants, while at the left are uninoeu- 

 lated ones, each ?> weeks old. 



teria, and in future all stock cultures intended for distribution by the 

 Office of Soil-Bacteriology and Plant-Xutrition Investigations to 

 farmers and other experimenters in the United States will be tested 

 in this manner. 



tCir. 120] 



