1907.] 



Flower Colour in Antirrhinum niajus 



293 



whole forms and delilas occurring in equal proportions. u Reversion " is 

 here due to the introduction of I by the white parent. 



From Case 1, on selfing, we should expect to obtain theoretically as the 

 result of the combination of four pairs of characters : — 







Ratios. 



Numbers 

 calculated. 



Numbers 

 observed. 



YILT ... 



YIL 



YIT 



YLT 



Y I 



Magenta . 



„ delila ... 

 Ivory 



81 or 118 '33 

 27 39 -44 

 36 52 -59 

 27 39 -44 



12 17 '53 

 9 13-15 



64 93 -50 



107 

 42 

 67 



42 



24 

 12 



80 



Ivory 



YT 



YL 



Yellow 



Crimson delila ... 

 Yellow 



Y 



White 







Totals 



256 373 98 



374 



From Case 2 we should obtain theoretically :- 







Eatios. 



Numbers 

 calculated. 



Numbers 

 observed. 



YITL ... 



YIL 



YTL 



YL 



Magenta 



27 or 206 '30 

 9 68 -76 

 9 68 -76 

 3 22 -92 



16 122 25 



229 



70 

 74 

 19 

 97 



„ delila... 

 Crimson 



„ delila... 

 White 









Totals 



64 488 -99 



489 



From Case 3 







Eatios. 



Numbers 

 calculated. 



Numbers 

 observed. 



YIL 



YI 



Magenta delila ... 



27 or 57 -80 

 9 19 -26 

 9 19 26 

 3 6-42 



16 34 -25 



59 

 19 

 18 

 7 

 34 



YL 



Crimson delila ... 

 Yellow .. 



Y 





White . 







Totals 



64 136 -99 



137 



