LUTHER BURBANK 



try your hand at fixing new types by careful in- 

 breeding and further selection. A very interest- 

 ing experiment may be made by planting all the 

 seeds from a single dahlia head in separate plots ; 

 carefully screening each plant against cross- 

 pollenation, and noting results in the second filial 

 generation. Each seed may seem to give a unique 

 variety, and by persistent selection through sev- 

 eral generations, following the same method, you 

 may secure an endless variety of interesting types. 

 Meantime, any individual that you prize may 

 serve as the progenitor, through root division, of 

 an entire race exactly like itself. 



STUDIES IN COLOR VARIATION" 



The dahlia also offers large possibilities for the 

 study of color variation, and for experiment in 

 the blending of different colors to produce new 

 types. As illustrating the possibilities of develop- 

 ment of this flower, it may be recalled that this 

 is one of the most recent acquisitions in the flower 

 garden, the dahlia having been brought under cul- 

 tivation only four or five human generations ago. 



The species of dahlia first introduced from 

 Mexico was brought to England in the year 1789 

 by the Marchioness of Butte. It had the general 

 form of a very large daisy, and it resembled 

 numerous familiar wild sunflower-like composites, 

 except that its floral envelope was dull scarlet with 

 a yellow center. Subsequently other species were 

 introduced, and through hybridization and selec- 



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