ON TIMBER TREES 
of unison with every other member of its own 
species, could we analyze its characteristics in 
detail, for every conspicuous point of divergence. 
If we consider minutiae of detail as to size and 
exact form of leaf and all the rest, no two individ- 
uals are identical. But if, on the other hand, we 
take the broad view, it is clear that each recognized 
species stands out in a place apart, grouped with 
all the other members of its own kind, and some- 
what isolated from all other species. 
Such being the obvious fact, it was perhaps not 
strange that the botanists and foresters of twenty- 
five years ago looked almost with suspicion on 
anyone who suggested that the different species of 
forest trees might be interbred and modified and 
used as material for building of new species that 
would better fulfill the conditions of re-forestra- 
tion than any existing species. 
Even botanists who thought that they fully 
grasped the idea of Darwinian evolution looked 
askance at such a suggestion. 
It seemed to bid defiance to the laws of 
heredity, as they understood them. 
It appeared almost like an affront to Nature 
herself to suggest that her handiwork might thus 
be modified and improved. 
MATERIALS For SELECTION 
And it may well be questioned whether this 
[161] 
