Star-Recessive, a Spontaneous Mutation in Drosophila Melanogaster

In a genetics experiment conducted in November 1937 with Drosophila melanogaster and involving the dominant mutant Star (S, in chromosome 2- at locus 1.3; causing an irregularity in the arrangement of eye facets and facet hairs, the homozygote being lethal), a number of flies appeared with small narrow eyes. When these were mated inter se, all of the F₁ had abnormal eyes, but these varied in size from that of S/+ (see Table 4) to a narrow slit of red pigment on which only a few facets were scattered. A clue to the manner of inheritance of the type with narrow eyes was found by mating a narrow-eye male to a wild-type female, with the result shown in Table 1.