Vermilion Gene and Gynandromorphism. 71 



gynandromorph was obtained in which the male parts showed 

 the sex-linked characters scute, echinus, cut, garnet, and forked. 

 These male parts included the whole head, in which region effects 

 of all five of these sex-linked genes could be identified with 

 certainty. Only one of these genes was present in the mother of 

 the gynandromorph, which was heterozygous for the sex-linked 

 genes eosin, ruby, forked, "vermilion lethal," and perhaps for 

 vermilion. All five of them were known to be present in the single 

 X of the father of the gynandromorph, which must therefore have 

 been the X present in the male parts of the gynandromorph itself. 

 But the X of the father was known to carry also the gene for 

 vermilion, and the eyes of the gynandromorph were not vermilion. 

 The not-vermilion color was, then, apparently determined not 

 by the genetic constitution of the eye-pigment itself, but by that 

 of some other portion of the body. 



I have obtained two other gynandromorphs in which vermilion 

 seems to have reacted in the same fashion; but these are not so 

 certain as the case described. One of them can be accounted for 

 by the rare type of "double-nucleus" gynandromorphism de- 

 scribed by Morgan and Bridges, and in the other the eye-color, 

 while not vermilion, was still not quite normal. 



Among the large number of gynandromorphs described by 

 Morgan and Bridges there are only three in which the male parts 

 were known to be genetically vermilion while the female parts 

 were not genetically vermilion, and in which these male parts 

 included eye tissue. In all of them, however, eosin eye color 

 was also present with the vermilion. Whether the eosin is re- 

 sponsible for the difference between these cases and the one re- 

 ported here, or whether that difference is due to a difference in 

 the genetic constitution of some other part of the body cannot be 

 determined as yet. 



