Abstract
In this paper, it is proved that the Curled wing (Cw), the Crayfish (cf) and Normal pupa are in the relation of multiple alleles. Consequently the symbol of the Curled wing (Cw) should be rewritten to cfCw from Cw.
Apparent irregularities of segregation can be accounted for by the assumption that the penetrance of cfCw is rather low, while that of cf is almost complete.