370 Jones and Skive.—Influence of Ammonium Sulphate 
Fig. 4. Distribution of the highest five yields of soy bean tops and roots from the cultures of 
series E, supplied with ferric phosphate as the source of iron for the plants. Yields of tops repre¬ 
sented by dotted areas, those of roots by stippled areas. 
Fig. 5. Distribution of the highest five yields of soy bean tops and roots from the cultures of 
series F, supplied with ferrous sulphate as the source of iron for the plants. Yields of tops repre¬ 
sented by dotted areas, those of roots by stippled areas. 
