310 CHARLES ZELENY 



Using factorial values and reducing facet numbers to departures 

 plus or minus from the mean value of the unselected white-bar 

 stock, the following percentage coefficients of dominance were 

 determined : 



a. Low selected bar (F24) over full eye 



_ full - heterozygote _ 26.67 - 19.44 ^ ^^^ 



~ full - low selected bar (F24) ~ 26.67 - (-4.45) 

 = 23.2 per cent. 

 h. Full eye over low selected bar (F24) 



low selected bar (F24) — heterozygote 

 low selected bar — full 



-4.45 - 19.44 ,^^ 



= X 100 = 76.8 per cent. 



-4.45 - 26.67 



TT1X 1 r n ^ull - heterozygote 



c. Ultra bar over lull eye = — — 



lull — ultra-bar 



+26.67 - (-4.26) .^n o. n 

 = J ^ i X 100 = 84.6 per cent. 



+26.67 - (-9.79) 



^ ,, ,, 1 ultra-bar — heterozygote 



a. ±ull eye over ultra-bar = — -— 



ultra-bar — lull 



-9.79 - (-4.26) ,n^ ,r A 



= ^ X 100 = 15.4 per cent. 



-9.79 - 26.67 



e. Ultra-bar over low selected bar (F2) 



_ low selected bar (F2) — heterozygote 



low selected bar — ultra-bar 



+0.74 - (-7.95) ,nn 00^ 



= ^ X 100 = 82.6 per cent. 



+0.74 - (-9.79) ^ 



/. Low selected bar (Fo) over ultra-bar 



ultra-bar — heterozygote 



ultra-bar — low selected bar (F2) 



-9.79 - (-7.95) ,^^ ,^, 



= ^ X 100 = 17.4 per cent. 



-9.79 - 0.74 



With three genes at the same locus all affecting facet number, 

 it is possible to make the interesting comparisons whose quanti- 

 tative values have just been determined. Obviously, domin- 

 ance has been strikingly increased by the change which trans- 

 formed bar into ultra-bar. Bar pulls full down only 23.2 per 



