Abstract
Genetic analysis of a new wing mutant, Surf wings (Srf), was performed. Mutant flies were extracted from a wild population of Drosophila melanogaster at the vicinity of Atomic Energy Research Institute, Seoul in August-September 1969. 1. The distal half of wings of heterozygotes (Srf/+) turned upwards about 40 degree from body axis, but flying ability was not disturbed. They overlap Cy in low frequency when they are grown below $22^{\circ}C$. This resembles with Si or j series, but wing margins are not rolled and diversed. Postscutellars are erected slightly, but they, in general, are not crossed. Any other external pleiotropic effects were not observed. 2. Penetrance and expressivity of both sexes are not complete. Their extents are variable with sex and temperature. These characters show maximum tendencies when the development is made at $22^{\circ}C$ (female: P = 0.996, E = 0.932, male:P = 0.961, E = 0.698). 3. The preliminary locus of Srf was determined to be 66.8 on the right arm of second chromosome by using recessive maker gene cn bw. 4. The homozygous flies(Srf/Srf) have shown perfect lethality. The heterozygotes (Srf/+), on the other hand, have shown to be viable and fertile. Srf chromosomes are kept in a balanced lethal system with Pm chromosomes which are associated with inversions. Hence, it is partially reasonable to suppose that Srf may persist in a natural population by the same mechanism. 5. Allelism test with Cy was also conducted. The fact that combination with Cy in the trans-phase (+ Srf/Cy +) is viable in contrast to the lethality of Srf/Srf and Pm/Pm indicates that Srf and Cy are not functionally allelic.