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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