Abstract: The geometrical projections of the wings of 71 species of selected mothswhich belong to 20 families in Heteroneura were made, and an orthogonal coordinate was established for each projection based on the longest diameter of projection and thevertical bisector of the diameter. Then three parameters (R_l, R₂, and R₃) were calculatedaccording to the wing areas in each quadrant (S_l, S₂, S₃ and S₄) as follows:R_l=(S₃-S₄)/(S_l+S₂)R=(S₃+S₄)/S₂, R₃=S₄/S₂. The hierarchical clusterings were conducted for 18 species of Pyralididae, 15species of Noctuidae, and all 71 tested species separately, based on the Euclidean distances or similarity coefficients of the three parameters (R_l, R₂ and R₃) of wing projection among species. The results showed that the migratory moths, Mythimna separata,Agrotis ypsilon and Cnaphalocrocis medinalis, always clustered in one group in clustering for either the fore wing or the combination of fore and hind wings. It is suggested that the shapes of the wings in migratory moths have some commongeometrical characters different from other tested lepidopterans. These common characters seem to be: (1) The anterior margin of the fore wing is rather straight, and thecostal area is narrower, and (2) The outer area of the fore wing is wider. These two characters are suitable to long-distance migratory flight of the migratory moths by air current.

Key words: Lepidoptera, Heteroneura, wing projection, cluster analysis