MENDELIAN LAWS OF INHERITANCE 293 



ness. If it meet with a gamete bearing W, the resulting plant 

 will be hybrid, and will not breed true. 



We thus see that on an average there will be formed from 

 the male gametes carrying the round character, uniting at 

 random with the female gametes available — 



I pure RR plants 

 1 hybrid RW „ 



Similarly, from the male gametes possessing the wrinkled 

 character (W) we should have — 



J pure WW plants I 

 [hybrid RW „ J 



Taking the combination of all the gametes at random, where 

 the number of male and female sex cells each bearing only one 

 (R or W) of two characters is the same, we should have the 

 following proportional result : — 



I plant ' 2 plants i plant 



RR RW WW 



Dominant. Recessive. 



As the round is dominant over the wrinkled character, the 

 impure hybrid plants (RW) will /oo^ like the pure (RR) plants. 

 Therefore the proportion of plants showing the round dominant 

 to those exhibiting the recessive wrinkled character would be 

 3 to I, which is what Mendel found to be actually the case in 

 his experiments. 



