LUTHER BURBANK 
ing the effect of hybridizing hundreds of other 
species, it is interesting to make inquiry as to why 
the first generation hybrids of the plum and 
almond showed such anomalous diversity. 
I am inclined to think that the answer may be 
found in the assumption that either one parent 
or the other was itself a hybrid. Perhaps both 
parents were hybrids. The fact that almonds are 
known to cross with the peach and the nectarine— 
to which reference will be made more at length 
presently—lends color to this assumption. And of 
course there is no question that the Japanese plums 
are largely hybridized. In a word, then, the 
hybrids produced by cross-pollenizing the Japan- 
ese plum and the almond were probably in reality 
second generation hybrids having the strains of 
other species than the almond and the Japanese 
plum in their veins. 
Be this as it may, the facts as to the curious 
diversity among the plum-almond hybrids have 
more than passing interest. 
It should further be recorded that the diversity 
in size was matched by the wide range of diversity 
in minor characteristics. The bark and leaves 
varied extensively among the different hybrids; 
on some trees the buds were round and plump, 
and on others long and sharp. Many of the trees 
produced somewhat abundant blossoms, and the 
[68] 
