114 



THE AMERICAN NATURALIST [Vol. XLIX 



the expectation. Yet the method employed in each case 

 was the same ; the history of each is the same. The only 

 difference is to be found in the fact that in the one case 

 the pink came from a more fertile parent ; in the other, 

 the red. 



The offspring of pairs "7" (Table XIV) and "2" 

 (Table XV) in which the ratios were 2.67: 1 and 4.26: 1, 

 respectively, were inbred for the F 3 . Fifteen pairs were 

 taken from each, bnt as there were among the red both 

 homozygous and heterozygous flies, only eight gave pink 

 in each case. The results follow: 



TABLE XVI 



Record of 8 Pairs Heterozygous Red-eyed F a op Pair "7" (Table XIV) 

 in Which the Ratio Was 2.67: 1 



























270 279 







5 19 



158 





3.47 : 1 











326 





426 



3.26 : 1 

















4.00 : 1 





135 143 



46 



49 



278 



95 



373 



2.93 : 1 





183 157 





50 



340 





439 



3.23 : 1 





172 154 











413 



3.74 : 1 





142 137 



43 



49 



279 



92 



371 



3.00 : 1 





57 | 46 



12 



16 



103 



28 



131 



3.67 : 1 



These results are significant, in that they show that the 

 original ratios, which their parents gave, were lost. 



