300 LUTHER BURBANK 



of the other. This was done season after sea- 

 son, seemingly with no effect whatever. 



At last, however, in the season of 1905, after 

 I had more than once half decided to relinquish 

 the effort to cross these plants, my perseverance 

 was rewarded. 



I had cross-pollenized the great African 

 stubbleberry, Solanum guinense, and the little 

 downy nightshade, Solanum villosum, as I had 

 done many times before, with no change or 

 added detail of method and for the moment I had 

 no reason to suppose that the efforts had been 

 more successful than before. 



But when the seeds were sprouted in the 

 greenhouse, a certain dozen or more plants were 

 discovered that differed from any I had seen 

 before. 



These plants were of a new type, and as they 

 developed it became increasingly clear that they 

 represented almost an exact compromise be- 

 tween the two parent species. 



There could be no question that they were the 

 hybrids which were so long sought. 



But the appearance of these hybrids was such 

 as to corroborate the belief, founded on my long 

 series of unsuccessful hybridizing experiments, 

 that the two Solanums I had finally mated were 

 so widely different in constitution as to stand at 



