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 raised from Primus always pro- 

 duced true like a wild species, even so that if 

 found wild all botanists everywhere would 

 classify it as a true species. 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 though difficult problems 



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