ON THE ORIGIN OF NEW SPECIES 



union of two diverse fruits does not within a 

 reasonable time satisfactorily respond, he drops 

 it, even though it may hold out ultimate pos- 

 sibilities. 



But important from a scientific and practi- 

 cal point of view as the plumcot is, it is over- 

 shadowed in scientific interest, in a sense, by 

 the "Primus" berry. This was an absolutely 

 new species of fruit, the first known recorded 

 species directly created by man. The primus 

 berry was made from the native California 

 dewberry and a Siberian raspberry. The two 

 were crossed by pollenation for the purpose of 

 developing, if possible, a distinct new fruit. 

 Seedlings were then raised from the cross, and 

 then followed years of selecting of the best 

 from the best. In the production of hybrid 

 raspberries or blackberries in general very 

 many species are drawn upon. For example, 

 he has worked upon over forty different black- 

 berries gathered from all over the world to 

 produce from among their many crosses new 

 hybrid types which should be better in various 

 ways than any of the ancestors, larger, finer 

 of flavor, more beautiful, better to ship. But 

 in this particular test he restricted the factors 



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