NEW CREATIONS IN PLANT LIFE 
kinds of trees already started on their way 
that it would not be worth while to make 
further crossings. 
In this connection it is of peculiar interest 
to note that Mr. Burbank has come to the 
conclusion, after many years of crossing, or 
hybridizing, and grafting, that hybridization 
in one sense is only a mode of grafting, botn 
being a more or less permanent combination. 
In an elaborate chart he traces side by side 
the parallelism of results he has noted in both 
grafting and pollenating: 
Where, for example, the pollen of one plant 
acts as a poison upon another, the grafts 
blight and die as if poisoned. 
Where, in pollenating, the union is partial, 
mosaic or temporary, seed is rarely produced, 
seedlings generally inheriting tendencies and 
qualities of one parent only, the second or 
later generations reverting fully; the grafting 
shows often a temporary union but not in 
normal condition. 
Where the union by crossing is free, seed- 
lings showing an unbalanced condition, 
varying widely, the best condition for scien- 
tific or natural selection, while the grafting 
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