Some Experiments of Euther Burbank 



hybrid, the ahen portion being finally entirely 

 rejected. It often happens in grafting, that the 

 branch will be united thoroughly at the point of 

 grafting, but in great stress, as the overbearing of 

 fruit, the grafted portion will separate and entirely 

 fallofF/' 



' ' In one sense, hybridization is only a mode of 

 grafting, both being a more or less permanent 

 combination. The different results from hybridi- 

 zation are shown in the diagram below." 



' ' Where the plants are very different, having 

 a different line of descent, and consequently differ- 

 ent structure, there will be no hydridization at all. 

 From this we have every gradation to the point 

 where the individuals are very closely alike, and 

 here we have scarcely any variation at all in the 

 progeny, a condition which favors extinction. 

 Again, in grafting, we have every intergradation 

 between total inability to unite and absolutely 

 perfect blend.'' 



' ' Sometimes a graft strengthens a plant by 

 increasing the body of foliage and thus strength- 



24 



