ON PEAS AND BEANS 



The cotyledons on each side were divided 

 uniformly in every case. 



Thus the influence of the poUenizing parent 

 was very markedly shown in the young vines from 

 the moment of their appearance. But after the 

 cotyledons had fallen, all evidence of the paternal 

 parentage of the plants disappeared. The vines 

 did, indeed, show unusual vigor throughout the 

 season, this, of course, suggesting their hybridity. 

 But as to appearance and characteristics in gen- 

 eral, with this exception, they were essentially 

 horticultural pole-beans like their maternal parent. 



The experiment was carried on for several 

 succeeding generations, but the progeny showed 

 no reversion to the traits of the lima bean. The 

 characteristics of the pole-bean had seemingly 

 been prepotent or dominant to an overwhelming 

 degree. 



This, then, would appear to be another case 

 in which a new race was formed in a single gen- 

 eration by the mingling of two widely divergent 

 racial strains. These hybrids of the lima and the 

 pole-bean may be compared, in that regard, to the 

 Plumcot and the Primus berry, to name only two 

 of the various allied instances that have come to 

 our attention. This is what I call a seed-graft- 

 hybrid. This and one other instance elsewhere 

 described are the only two similar ones that ever 



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