308 LUTHER BURBANK 



practical commercial production. Yet it seems 

 not unlikely that a more extended series of ex- 

 periments in hybridizing and selection in which 

 strains of the Darwin potato are introduced 

 might result in a product of great value. 



Some of the improved Darwin seedlings pro- 

 duced tubers of exceptional size, though, as 

 before stated, much subject to decay. If the 

 breeding experiments were conducted along right 

 lines it would probably be possible to produce in 

 later generations a hybrid that combined the 

 large size of tuber of the improved Darwin with 

 the keeping qualities of the cultivated potato. 

 It is really of great importance that the experi- 

 ments should be repeated and carried forward to 

 a successful issue. 



What has just been said as to the curious re- 

 sults of hybridizing experiments with this species 

 sufficiently indicate that experiments of this kind 

 will not be lacking in interest. 



Extensive hybridizing experiments were also 

 carried on, using the Solarium Commersoni, a 

 species growing wild in the region of the Mer- 

 cedes River, in South America; these for a time 

 gave great promise. The hybrids of this plant and 

 the cultivated potato showed great improvement 

 in some directions, but all the seedlings lacked 

 one desirable character or another. The chief trou- 



