LUTHER BURBANK 



their Mendelian factors for size and character of 

 vine, but retain mixed factors for color of seed. 



No one as yet, however, has worked out in 

 detail the combinations of hereditary factors for 

 the bean as Mendel worked it out in the case of 

 the pea. Such an investigation would constitute 

 one of the most interesting experiments in plant 

 breeding that any one who has time for it could 

 undertake. It is true that the hybridizing of the 

 plant of this genus is rather difficult, inasmuch as 

 the flowers must be opened and the stamens 

 removed with a pair of small forceps to avoid 

 self-fertilization. 



But, on the other hand, once cross-fertUization 

 has been effected there are obvious advantages in 

 later generations in working with a plant that is 

 normally self-fertilized, the pollen of which is 

 inaccessible to insects. 



All in all, I think the bean offers as many 

 inducements for improvement as any other plant 

 under cultivation. 



— Although much has been and 

 may be accomplished with peas 

 and beans by mere selection, 

 these plants offer exceptional 

 opportunities also for improve- 

 ment through hybridization. 



