in Hybridisation 61 



From the angular yellow seeds 96 resulting plants bore 

 seed, of which : 



28 had only angular yellow seeds aB 



68 angular yellow and green seeds aBb. 



From 108 round green seeds 102 resulting plants fruited, 

 of which : 



35 had only round green seeds Ab 



67 round and angular green seeds Aab. 



The angular green seeds yielded 30 plants which bore seeds 

 all of like character ; they remained constant ab. 



The offspring of the hybrids appeared therefore under 

 nine different forms, some of them in very unequal numbers. 

 When these are collected and co-ordinated we find : 



38 plants with the sign AB 



35 Ab 



28 aB 



30 ab 



65 ABb 



68 aBb 



60 AaB 



67 Aab 



138 AaBb. 



The whole of the forms may be classed into three 

 essentially different groups. The first embraces those with 

 the signs AB, Ab, aB, and ab : they possess only constant 

 characters and do not vary again in the next generation. 

 Each of these forms is represented on the average thirty- 

 three times. The second group embraces the signs ABb, 

 aBb, AaB, Aab : these are constant in one character and 

 hybrid in another, and vary in the next generation only 

 as regards the hybrid character. Each of these appears on 



