MENDELISM 



Now, as the table shows, it is possible to express the 

 gametic series by a general formula j^t \*PfAB + Ab + aB + ( 

 ( - i) ab, where 2n is the total number of the gametes in the 

 series. A plant producing such a series of gametes gives 

 rise to a family of zygotes in which 3 2 - (zn - i) show 

 both of the dominant characters and 2 -(2- i) show 

 both of the recessive characters, while the number of the 

 two classes which each show one of the two dominants is 

 (zn - i). When in such a series the coupling becomes 

 closer the value of ;/ increases, but in comparison with n 2 

 its value becomes less and less. The larger n becomes 

 the more negligible is its value relatively to n 2 . If, there- 

 fore, the coupling were very close, the series 3 2 - (2n - i) : 

 (2 - i) : (zn - i) : n 2 - (zn - i) would approximate more 

 and more to the series 3 2 : 2 , i.e. to a simple 3 : i ratio. 

 Though the point is probably of more theoretical than 

 practical interest, it is not impossible that some of the cases 

 which have hitherto been regarded as following a simple 

 3 : i ratio will turn out on further analysis to belong to this 

 more complicated scheme. 



