PLATE XXXIX 



Fig. I. — Root system of a com plant that had reached a height of 3 feet 6 inches. 

 Seed planted May 23, 1914. Root system isolated on July 17, 1914. Greatest depth 

 of root penetration, 3 feet. Greatest lateral extent of the roots, 3 feet 6 inches. 



Fig. 2 . — Root systems of two corn plants with a height of i foot 6 inches. Seed 

 planted on May 26, 1915. Root systems obtained on July 10, 1915. Greatest depth 

 of roots, I foot 3 inches. Greatest lateral extent of roots, 2 feet 10 inches. 



Fig. 3. — Root system of a Dwarf milo plant at the age of 4 weeks. Seed planted 

 on May 23, 1914. Root system obtained on June 24, 1914. Plant stood i foot high. 

 Greatest depth of root penetration, i foot 6 inches. Greatest lateral extent of roots, 

 3 feet. 



Fig. 4. — Root systems of two Blackhull kafir plants i foot in height. Seed planted 

 on May 26, 1915. Root systems isolated on July 10, 1915. Greatest depth of root 

 penetration, i foot 6 inches. Greatest lateral extent of roots, 2 feet. 



