LUTHER BURBANK 



of a small strip of an unusual color appearing on 

 blossoms otherwise of a fixed hue. 



But the same method of selection may some- 

 times be applied to the improvement of the shade 

 of color, or even to the development of a new color, 

 from a flower that shows only a faint departure 

 in shade from the normal. And the same principle 

 of selection, followed out in precisely the same 

 manner, applies to the development of flowers or 

 fruits of varying size, of larger or smaller stem, 

 abundance of blossom, profusion of leaf or flower 

 or fruit, and the like. 



It is equally possible to alter the proportions 

 of the chemical constituents of a plant in certain 

 instances. 



The case of my sugar prunes, which were 

 developed to have a sugar content of more than 

 23 per cent, as against the 15 per cent, of their 

 ancestral type, will be recalled. In a similar 

 way the sugar beet has by mere selection been 

 developed until the races now cultivated contain 

 several times the proportion of sugar of the 

 ancestral beets even of twenty years ago. 



An interesting experiment in causing the 

 progeny of a certain plant to vary in opposite 

 directions through selection, has been made at 

 the Illinois Agricultural Station. Here the quality 

 under consideration was the protein content — that 



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