No. 594] THE 3LECIIAXISM OF CROSSIXChOVER 3 



ent combinations of factors in group I with factors 

 group II. 



| ywAbvmsrf 186 | 



Double 



Not only the independence of the factors in the two 

 groups was shown by thk* experiment in which the two 

 groups were followed at once, but also the independence of 

 the crossings-over. In the total of 166 cases, there were 

 81 in which chromosome I underwent crossing-over (either 



