MENDEL'S LAW OF HEEEDITY 



ingly difficult thing it is to fix types obtained by 

 crossing, if the number of dominant characters 



Omnocen 



FIG. 34. Diagram to show the gametic combinations and 

 segregations involved in a cross between guinea-pigs differ- 

 ing in three unit-characters. L stands for long hair, S for 

 short hair, W for white hair, and D for dark hair; R for 

 rough, and Sm for smooth coat. Compare Figs. 22 and 32. 



in the selected type increases. On the theory of 

 unit-characters the gametic combinations and 

 segregations involved in this cross are as shown 



49 



