ON THE QUINCE 



No bush or tree of the entire lot put forth a 

 single blossom. 



Other Dwarfs Recalled 



It is interesting to recall, in connection with 

 the curious result of this experiment in hybridiz- 

 ing the quinces of widely varying species, the re- 

 sults of my hybridization of the California and 

 Persian walnuts. 



It will be remembered that the hybrids thus 

 produced were of extraordinary growth, but that 

 they produced very few nuts, and that among the 

 seedlings of the second generation there were 

 many trees of dwarfed growth, suggesting the 

 quince hybrids. 



We found reason to believe that the curious 

 result of hybridizing the walnuts might be ex- 

 plained on the supposition that the parent forms 

 had diverged almost to the point of mutual antag- 

 onism. They had not varied quite to the point 

 where their offspring were sterile, but they were 

 approaching that limit. 



The quinces of the experiment now under con- 

 sideration had diverged one stage farther. They 

 are still within the limits of affinity that permit 

 cross-fertilization, but not within those that per- 

 mit the production of fertile offspring. Their case 

 is rather to be likened to that of pur petunia and 

 tobacco hybrids, which, as the reader will recol- 



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