1 72 Plant-Breeding 



yellow (RY) X angular green (ry) = RrYy appearing as 

 round and yellow in FI. 



Gametes of F\ = RR, Ry, rY, and ry. 



Visible types of F 2 = 9 (apparently) RY, 3 Ry, 3 rY, 

 and 1 ry. 



The following were actually found by Mendel in F 2 : 



RY, round and yellow, 315. 



rY, angular and yellow, 101. 



Ry, round and green, 108. 



ry, angular and green, 32. 



These figures stand approximately in the ratio of 9 RY : 

 3 rY : 3 Ry : 1 ry, but these forms, which appeared to be 

 only four classes, were found in the next generation to be 

 made up of nine really different classes. 



From the round yellow seeds (apparently RY) there 

 were obtained in the next year : 



1. RY, round and yellow seeds, 38 



2. RYy, round, yellow and green seeds, 65 



3. RrYj round, yellow and angular seeds, 60 



4. RrYy, round, yellow and green angular, yellow 

 and green, 138 



From the round and green seeds (apparently Ry) were 

 obtained : 



5. Ry, round and green seeds, 35 



6. Rry, round angular and green seeds, 67 

 From the angular and yellow seeds (apparently rY) 



were obtained : 



7. rY, angular and yellow seeds, 28 



8. rYy, angular and yellow-green seeds, 67 

 From the angular and green ry seeds were obtained : 



9. ry, angular and green seeds, 30 



