LUTHER BURBANK 
with its relative, the mulberry, did not prove 
successful. 
But this was probably because I did not give 
enough time and patient attention to the effort. 
The two fruits are botanically related and I some- 
times think of the fig as a mulberry turned outside 
in. 
It should be possible to effect hybridization 
between the two species, and perhaps greatly to 
improve one or both of them; possibly even to 
develop a wholly new fruit through this union— 
like the plumcot. 
Movine TropicaL Fruirs NORTHWARD 
We need not enter into further details in 
connection with the subject of tropical fruits be- 
cause I am chiefly concerned in this narrative to 
tell what I have accomplished in the way of plant 
development rather than to dwell on unrealized 
possibilities. But I cannot refrain from urging 
upon others who are geographically so located as 
to bring the tender fruits within the range of their 
experiments, the desirability of undertaking ex- 
tensive series of investigations in this practically 
untrodden field. 
It should be recalled that all of our fruits, even 
the hardiest ones that now penetrate to the Arctic 
Zone, must have come originally from the Tropics. 
The fact that the plum and pear and apple 
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