LUTHER BURBANK 



All in all, then, the columbine offers most in- 

 teresting possibilities for the experimenter who 

 likes to test for himself the principles of heredity. 

 In the matter of color, there is the widest variation, 

 some of the familiar forms being blue, others red 

 and yellow. The curious spurs that characterize 

 the flower, and the fact that some varieties lack 

 them, furnish tangible features that may be tested, 

 and the single versus the double corolla constitutes 

 a third feature that is also susceptible to definite 

 observation and record. 



So the experimenter who will work with a 

 small number, differing as to characteristics of 

 color and spur and doubleness, has opportunity 

 for watching the interplay of hereditary forces; 

 observing the dominance of certain hereditary fac- 

 tors, and the recessiveness of their opposing fac- 

 tors; and finally the segregation of the different 

 characters and their reassembling in new com- 

 binations in the second generation, that will test 

 his knowledge of the principles of heredity to the 

 utmost, and at the same time will give him definite 

 ideas about the practicalities of plant develop- 

 ment that will be at once interesting and valuable. 



Meantime the experimenter may introduce 

 problems of far greater complexity if he so desires 

 by mixing larger numbers of the plants somewhat 

 at random, and allowing them to be cross-fertilized 



[56] 



