528 



EVOLUTION 



We now believe that our cultivated plants afford many ex- 

 amples of mutations. Strawberries without runners have sud- 

 denly arisen among plants with runners and have bred true from 

 seed. The Beseler Oats, a beardless variety, originated from a few 

 plants found in a field of bearded Oats. Also a number of choice 

 new varieties of Wheat started from one or a few plants which 



FIG. 471. The Wild Cabbage and some of the forms that are supposed to 

 be mutants of the Wild Cabbage. A, Wild Cabbage; B, Kohlrabi; C, Cauli- 

 flower; D, Cabbage; E, Welsh or Savoy Cabbage; F, Brussels Sprouts. 

 After Smalian. 



suddenly appeared differing in characters from the other plants 

 of the field. The Cauliflower and Kohlrabi (Fig. Ifi '!) were 

 raised from isolated monstrosities of the wild Cabbage (Brassica 

 oleracea). Green Roses, green Dahlias, seedless Oranges, seed- 

 less Bananas, and varieties of the Boston Fern with finely divided 

 leaves are other examples of mutations. Sometimes a bud may 

 mutate, giving rise to a bud sport. In this way the Nectarine, 

 which has a fruit resembling that of the Peach but lacking 



