LINKAGE OF THE FACTOR FOR BIFID WING. 



155 



gave rise to the four possible classes of males as shown in Table 

 VII. 



TABLE VII. 



To ILLUSTRATE EXPERIMENT IV. 



P 1 



F 1 



LYX - LYX = LY 9 

 Gametes LYX 



LYX -- BfGrX == LGr 9 



(i) LYX. (2) BfGrX, 

 Fi Eggs i 



I (3) LGrX, (4 



BfGrX - o = BfGrd" 

 BfGrX, o 



LYX - o = LYc? 

 LYX, o 



LYX - LYX 



BfYX - LYX 



LGrX - LYX | 



BrGrX - LYX / 



=t LY9 

 = LGr 9 



LYX - o = 



BfGrX - o = BfGrc? 



LGrX - o = LGrc? 



BfYX - o = BfYcT 



The actual results of the experiment are shown in Table VIII. 



TABLE VIII. 



RESULTS OF EXPERIMENT IV. 

 LY 9 X BfGrc? 

 LGr 9 X LYc? 



Table VIII. shows that the linkage of the factors for bifid and 

 yellow is stronger than for bifid and vermilion studied in Experi- 

 ment I., the per cent, of crossovers being 5. 



On mating males of the crossover class BfY with pure LR 

 females we find in the F 2 generation (Table IX.) that the new 

 combination persists in the same percentage as did the original 

 combinations depicted in Table VIII. These results are in 

 harmony with those obtained in Experiment I. 



