HOW MAY I DO IT, TOO;—GRAFTING 
shows a ready union of cion and tree but 
separation follows under unusual _ stress, 
drought, overbearing, lack of nourishment, 
and so on. 
In another stage of usual variation where, 
in crossing, the union is free, the seed of 
superior germinating quality and produced 
abundantly, the seedlings being normal with 
ordinary amount of ‘variability, the grafts 
unite readily, thriving well; sometimes better 
than when grafted on their own stock. 
He says on this point: 
“Where the plants are very different, having 
a different line of descent and consequently 
different structure, there will be no hybridiza- 
tion at all. From this we have every grada- 
tion to a point where the individuals are very 
closely alike, and here we also 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.” 
Along with all the work of grafting goes 
constant selection, the constant choosing of 
the best from the best. It might be somewhat 
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