Evolution: The Quest of Truth 159 



Many garden plants and most domestic ani- 

 mals are further removed from their parental 

 stems than the strawberry is, but history often 

 supplies the connecting evidence and enables 

 us to identify the offspring with the ancestry. 

 But when history is silent, we may be able 

 only to guess what the original form may have 

 been, or we may say that the parental species is 

 extinct. It is probable that very few of the 

 original forms of our domestic plants are actu- 

 ally extinct, but the evolution has been so great 

 that we can no longer trace it. 



It is most significant that of very many of 

 the common and long domesticated plants we 

 do not positively know the wild originals. Of 

 such plants are apple, peach, apricot, almond, 

 orange, lemon, wheat, rye, barley, bean, wine- 

 grape, Indian corn, cotton, flax, sugar-cane, 

 tobacco, sweet potato, banana, pumpkin and 

 squash, and many more. And who knows 

 what was the ancestral form of the ox, sheep, 

 cat, and dog ? 



I must not be understood as saying that 

 there are no distinct types in nature, or that it 



