LUTHER BURBANK 



curious series of minute oil wells laden with es- 

 sential essences of no less individual quality. 



These traits, among others, mark the citrus 

 fruits as constituting a highly specialized and iso- 

 lated group of plants. 



It is not to be expected that any one of them 

 could be hybridized with a member of any other 

 family. But, on the other hand, within the bounds 

 of the citrus family there is full opportunity, as I 

 have already pointed out, for cross-fertilization. 



I am confident that many interesting develop- 

 ments would have resulted from the hybridization 

 of oranges and lemons and limes and citrons in 

 my orchard had not the frost treated the tender- 

 lings so harshly. Not unlikely there would have 

 been developed new citrus fruits differing from 

 any existing one as markedly as the plumcot dif- 

 fers from apricot and plum. This, of course, is 

 only matter of conjecture for the experiments were 

 cut short, as already told, before they passed be- 

 yond the early stages. 



Still the fact that I was able to effect hybridiza- 

 tion between the various citrus fruits is highly 

 suggestive and should prove stimulative to other 

 workers. 



Here is a field as yet scarcely entered and one 

 that offers almost unbounded possibilities. The 

 orange industry is the great fruit industry of Cali- 



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