12 Plant-Breeding 



The reader is curious to know how this original tree came 

 to be, and this we may find out before we are done ; but 

 for the present, let it be said that it is equally possible for 

 it to have come from a seed, or to have sprung from a 

 branch which some person had noticed to be very dif- 

 ferent from the associated branches in the tree-top. In 

 other words, the ultimate unit or individual of variation 

 is the bud and the bit of wood or tissue to which it is 

 attached; for every bud, like every seed, produces an 

 offspring that can be distinguished from every other 

 offspring whatsoever. 



