HYBRIDIZATION 579 



viduals are selected. After continuing the selection for a few 

 generations, a race with a certain standard and steadiness is 

 obtained. The race obtained by this method of selection is 

 the progeny of a single individual, and its desirable features are 

 more stable than in most races secured by mass selection. This 

 method also requires less labor and usually less time than the 

 method of mass culture. After the race is secured by pedigree 

 culture, it is usually tested in mass culture to see how it behaves 

 when grown in masses under ordinary field conditions. 



Selection of Mutants. — Many valuable races of plants have 

 been discovered accidentally and apparently have arisen sud- 

 denly. The Fultz Wheat comes from a few plants which were 

 accidentally discovered growing in a field of Lancaster Red. 

 These few plants, which were smoother and had more beautiful 

 heads than the Lancaster Red, were saved for seed, and from 

 these seeds the well-known and valuable race of Fultz Wheat 

 originated. The Gold Coin Wheat was accidentally found 

 growing in a field of Mediterranean Wheat. There are a num- 

 ber of varieties of Wheat, Oats, Barley, and Rye which appar- 

 ently originated in a similar way. 



Many or all of the different cultivated varieties of Dewber- 

 ries were accidentally found growing wild and were selected 

 because they showed some desirable features not possessed by 

 the ordinary type of wild Dewberries. Some may be hybrids, 

 while others are most likely mutants. 



In woody plants, such as fruit trees, the selection of vegeta- 

 tive mutations known as bud sports, in which a branch may 

 produce a type of fruit different from the fruit produced by 

 other branches, often leads to the estabhshment of new varieties. 

 By propagating these special branches by grafting, a different 

 type of tree may be obtained. The Nectarine has already been 

 mentioned as arising in this way, and there still are other ex- 

 amples among Peaches, Apples, and other fruits. Greening 

 Apples often have branches bearing Russet Apples, and Russet 

 Apples often have branches bearing Greening Apples. There 

 are, therefore, many instances in which selection has not only 

 resulted- in the securing of better grains, vegetables, fruits, and 

 ornamental plants, but also in new types. 



Hybridization. — The advantage of hybridization is that by 

 crossing one can combine in the offspring the different desirable 



