336 MUTATIONS IN EYE-COLOR OF DROSOPHILA. 



Other Tests of the ft Pink-Orange Cross. 



The following data are of interest in that they confirm the general scheme of 

 explanation. The ft pink females were tested with red and with vermilion flies 

 of pure strains. The experiments were made by Mr. A. H. Sturtevant to whom 

 I am indebted for the data: 



When P 9 (from 9 by P & ) was crossed to R & , the following classes 

 were produced: 



Red 9 98 Red cf 66 Vermilion <*• 34 



The analysis of the combination follows : 



vpOX — vpOX Orange 9 ) p 



vPOX — vpo Pink & 



vpOXvPOX Pink 9 (ft) 



VPOXVpo Red of (pure strain) 



vpOXVPOX Red 9 



vPOXVPOX Red 9 



vpOXVpo Vermilion & 



vPOX Vpo Red cf 



F 



The expectation is that the red females equal the sum of the other two classes 

 and this is closely realized; the vermilion males run behind however and this 

 deficiency may seem (?) to be made good by the excess of the red males. 



When P 9 (from 9 by P <? ) is mated to vermilion <? of a pure strain the 

 offspring were : 



Red 9 74 Red <? 54 Vermilion 9 57 Vermilion d 1 34 



The males run behind the females, and the vermilion behind the reds 

 The analysis is as follows : 



vpOX — vpOX Orange 9 \ p 



Pink d 1 



vpOXvPOX Pink 9 (ft) 



VpOXVpo Vermilion & (pure) 



F 



vpOXVpOX Vermilion 9 



vPOXVpOX Red 9 



vpOXVpo Vermilion <? 



vPOXVpo Red d" 



When P 9 's (from P 9 by d> ) are mated to red males of pure strain the 



results were : 



Red 9 38 Red tf 12 Vermilion & 17 



