And it got better . . .
In 1913, Morganís student Alfred Sturtevant took a female that was heterozygous for both traits (X+/+Xv/y) and crossed her with a male that showed both traits (Xv/yY)
Since both vermillion eyes and yellow body are sex-linked, they should both be located on the X chromosome.
This means that you might expect to get only flies that were both yellow-bodied and vermillion-eyed, or both tan-bodied and red-eyed