LUTHER BURBANK 



accompany him. This was the final stage of the 

 eastward journey of our remote ancestors which 

 carried them across a land bridge, now no longer 

 in existence, between northeastern Asia and the 

 present Alaska, and thus brought them to 

 America. 



It seems a fair presumption that when prehis- 

 toric man made this final migration he brought 

 the apple with him. 



At all events, with or without man's aid, the 

 apple made its way across the bridge that joined 

 the continents. 



Probably the fact that the seeds of the pear 

 will not germinate when once dried may explain 

 the failure of that tree to come with the forerun- 

 ners of the Indian to the new continent. 



The seeds of all orchard fruits germinate far 

 better if they have not been too thoroughly dried. 

 But the seed of the pear is peculiarly susceptible 

 to destruction through drying; and if the ancestral 

 pear had the same quality, which we need not 

 doubt, this fact may in itself have been instru- 

 mental in restricting the spread of a tree which, 

 when introduced in America in modern times, 

 proved thoroughly adapted to our soil and climate. 



We must not press this point too far, however, 

 for the plum seed also dies if dried; yet the plum 

 came to America in prehistoric times along with 



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