in Hybridisation 333 



a short stem, terminal white flowers, and simply inflated 

 pods ; the pollen plant, on the other hand, a long stem, 

 violet-red flowers distributed along the stem, and con- 

 stricted pods ; the hybrid resembles the seed parent only in 

 the form of the pod ; in the other characters it agrees with 

 the pollen parent. Should one of the two parental types 

 possess only dominant characters, then the hybrid is scarcely 

 or not at all distinguishable from it. 



Two experiments were made with a considerable number 

 of plants. In the first experiment the parental plants differed 

 in the form of the seed and in the colour of the albumen ; in 

 the second in the form of the seed, in the colour of the 

 albumen, and in the colour of the seed-coats. Experiments 

 with seed characters give the result in the simplest and 

 most certain way. 



In order to facilitate study of the data in these experi- 

 ments, the different characters of the seed plant will be 

 indicated by A, B, C, those of the pollen plant by a, 6, c, 

 and the hybrid forms of the characters by Aa, Bb, and Cc. 



Expt. i. AB, seed parents; ad, pollen parents; 



A, form round ; a, form wrinkled ; 



B, albumen yellow. b, albumen green. 



The fertilised seeds appeared round and yellow like those 

 of the seed parents. The plants raised therefrom yielded 

 seeds of four sorts, which frequently presented themselves 

 in one pod. In all, 556 seeds were yielded by 15 plants, 

 and of these there were : 



315 round and yellow, 

 101 wrinkled and yellow, 

 1 08 round and green, 

 32 wrinkled and green. 



All were sown the following year. Eleven of the round 

 yellow seeds did not yield plants, and three plants did not 

 form seeds. Among the rest: 



38 had round yellow seeds . . . AB 



65 round yellow and green seeds . . ABb 



60 round yellow and wrinkled yellow seeds AaB 

 138 round yellow and green, wrinkled yellow 



and green seeds .... AaBb. 



