Some Laws oe Heredity 



41 



bers. It is a matter of chance which sort of 

 sperm will fertilize either sort of egg when these 

 hybrid offspring shall produce their progeny. 

 The possible combinations in such an event are 

 portrayed in the following scheme : 



The results are one fertilized egg with a 

 double dose of the determiner, two that have a 

 single dose, and one that has no yellow deter- 

 miner. Now since the presence of the yellow 

 determiner makes the plant yeUow-seeded even 

 if present in only a single dose we should expect 

 the Mendehan ratio of three yeUow-seeded 

 plants to one green-seeded in the F^ generation. 

 It is also plain why the green-seeded plants only 

 produce green-seeded offspring, for they have 

 no yellow determiner in them. It is also 



