ON SPECIFIC NEEDS 
he can modify the core or stone that lies at its 
center. 
Yet from man’s standpoint this inevitable cen- 
tral structure, forming the heart of every orchard 
fruit, is a conspicuous detriment. And it is alto- 
gether desirable that fruits should be developed 
in which the stony or fibrous covering of the seed 
is eliminated, or in which the substance of the 
seed itself has been substituted by juicy tissues. 
Everyone knows that this much desired modifi- 
cation has been effected, or all but effected, in the 
case of the so-called navel orange. An accidentally 
discovered mutant, doubtless a pathological speci- 
men, was seized on by some keen-eyed observer, 
and a race of seedless oranges was developed by 
selection, and widely disseminated by grafting. 
Also there are seedless grapes. 
The reader will recall the long series of experi- 
ments through which I was enabled, by taking 
advantage of a similar malformation in a wild 
European plum, to develop by hybridization and 
selective breeding a race of stoneless plums. 
Everyone knows, also, that there comes to us 
from the tropics a familiar fruit, the banana, that 
is seedless; although perhaps it is not so well 
known that this fruit has lost its seed through 
being propagated for long generations by division. 
The precise steps through which this development 
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