266 THE POPULAR SCIENCE MONTHLY 



Since the Primus species was originated, numerous similar cases 

 have attracted attention, such as my now popular Phenomenal pro- 

 duced by crossing the Cuthbert raspberry with our native Pacific coast 

 blackberry, and the Logan berry, both of which, though a complete 

 blend of two such distinct species, yet reproduce from seed as truly as 

 any wild rubus species. 



I have had also growing on my grounds for some fifteen years or 

 more hybrids of Rubus idceus and Rubus villosus, both red and yellow 

 varieties. All are exactly intermediate between these two very widely 

 different species, yet both always come true intermediates from seed, 

 generation after generation, never reverting either way: 



By crossing the great African " stubble berry " (Solanum guinense) 

 with our Pacific coast "rabbit weed" (Solanum villosum) an abso- 

 lutely new species has also been produced, the fruit of which resembles 

 in almost every particular the common blueberry (Vaccinium Penn- 

 sylvanicum) , and while the fruit of neither parent species is edible, the 

 fruit of the newly created one is most delicious and most abundantly 

 produced, and the seedlings, generation after generation though pro- 

 duced by the million, still, all come as true to the new type as do 

 either parent species to their normal type. 



Still another example of this mode may be found in my experiments 

 with opuntias. By crossing 0. tuna with 0. vulgaris, thousands of seed- 

 lings have been produced, all of which, in the first, second and third 

 generations, though a well-balanced blend of the two natural species, still 

 come as true to the newly created species as do either parent species to 

 their own natural types. 



Not only does this new mode hold true under cultivation but species 

 are also summarily produced in a wild state by natural crossing. 



The western blackcap (Rubus occidentalis) and the eastern red 

 raspberry (Rubus strigosus) when growing contiguous, as they very 

 commonly do in Central British America, often cross, forming an 

 intermediate new species which sometimes sorely crowds both of the 

 parent species, and when brought under cultivation still firmly main- 

 tains its intermediate characters, no matter how often reproduced from 

 seed. And still further, our common "tarweed" (Madia elegans) 

 with its beautiful large blossoms often crosses with M. saliva with 

 its insignificant pale yellow flowers, producing a complete intermediate. 

 I have not yet determined whether the intermediate will reproduce 

 true from seed, but confidently expect it to do so. Similar results 

 among wild evergreens and deciduous trees and shrubs and herbaceous 

 plants have been frequently and forcefully brought to my attention, 

 leaving little doubt in my own mind that the evolution of species is by 

 more modes than some are inclined to admit. 



