SCOPE OF GENETICS 39 



from a district where lacticolor does not 

 exist, the result was that all the males were 

 gi'ossidariata and all the females lacticolor \ 

 It is difficult to follow the course of such an 

 experiment on once hearing and all I ask 

 you to remember is first that there is a series 

 of matings giving very curious distributions 

 of the characters of type and variety among 

 the two sexes. And then, what is perhaps 

 the most singular fact of all, that the wild 

 typical grossidarlata female can when crossed 

 with the lacticolor male produce all females 

 lacticolor. This last fact can, we know, mean 

 only one thing, namely that these wild females 

 are in reality hybrids of lacticolor \ though 

 since the males are pure grossulariata, that 

 fact would in the natural course of things 

 never be revealed. 



When we encounter such a series of 

 phenomena as this, our business is to find 

 a means of symbolical expression which will 



r-^- 



