PLATE 20 



('liriit>ot]uim)ni-s nauncofius var. viriduJus. Plant H-3. To illustrate incthod 

 for increasing weight of rubber-bearing parts. 



Fig. 1. Tlie wild plant as it appeared February l(i, 1918. Height 5i/^ feet, 

 spread 5 feet. 



Fig. 2. The same plant after pruning, February 16, 1918. Greatest height 3^^ 

 feet. The cut brant-hes are 276 in number, one to three years old, and average 

 one half inch thick. 



Fig. 3. The same plant September 16, 1918. Height 4 feet 3 inches, spread 

 ■4 feet 6 inches. The number of branches has increased to 640. This increase is 

 somewhat greater than in other plants subjected to the same treatment. 



The black stake in figs. 1 and 2 is 40 cm. high. The short stake in all three 

 figures is 4 inches high. 



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