SELECTIVE EVOLUTION 207 



The bees help us to make new daisy colors be- 

 cause, through heredity, the daisies of our first 

 planting gave daisy nectar, though their colors 

 were white and orange. And in a few cases 

 which we might try, we could safely intrust the 

 work of pollination to the bees, or birds, or other 

 messengers with whom the plants have built up 

 partnerships. 



But in the most important we should find that 

 the pollination would have to be done only by 

 hand. 



If, for example, we desired to effect a com- 

 bination between two flowers, one of which 

 blooms in the spring and the other in midsum- 

 mer, the bees could be of no service. We should 

 have to take the pollen of the early blooming 

 flower and carefully save it until it could be ap- 

 plied to the other. 



If we desired to effect a combination between 

 a bird flower and a bee flower, even if in bloom 

 at the same time, we should find it necessary to 

 attend to the pollination ourselves. 



If we had it in mind to effect a cross between 

 a particularly large, insipid plum and a small, 

 highly flavored plum of another species, or if we 

 desired to effect a cross between any two selected 

 parents, we should find it necessary to do our own 

 work of pollination. 



