PEAS AND BEANS 151 



The cotyledons on each side were divided 

 uniformly in every case. 



Thus the influence of the pollenizing 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 very unusual vigor 

 throughout the season, this, of course, suggesting 

 their hybridity. But as to appearance and char- 

 acteristics in general, 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 else- 



