6 



A MANUAL OF MENDELISM 



the first series of experiments while the other carried 

 the two corresponding recessives, and, as is to have 

 been expected, the hybrids bore the two dominant 

 characters only — the recessives both disappearing ; but, 

 when they in their turn were bred from, their progeny 

 consisted of four groups bearing the characters given in 

 the following table and standing to each other numeri- 

 cally in the ratio 9:8:3:1, thus : 



Round 



Round Wrinkled Wrinkled 



I.e. 



This again raised the question : Were the hybrids' 

 progeny hybrid or pure ? To answer it, their seeds 

 were sown, and, from the generation so produced, just 

 as in the first series of experiments, some were found to 

 be hybrid while others bred true. And not only so ; 

 for it was also found, although there were now four 

 groups of hybrids' progeny, that each group again con- 

 tained equal numbers of true-breeding individuals. The 

 following table gives the number bred from and the 

 number which bred true : 



Round Round Wrinkled Wrinkled 

 with with with with 



yellow green yellow green 



albumen albumen albumen albumen 

 Bred from : 301 102 96 30 



Breeding true : 38 35 28 30 



In this experiment, three results similar to those in 

 the first series are to be noted, namely : 



