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A mixture of two different rare gas elements produces a characteristic emission spectrum when excited by an electric discharge. Such spectra were observed in seven out of the ten possible combinations. The spectra consist of four band groups, except for mixtures with helium in which only two groups were observable. In view of the excitation conditions, band energies, and their appearances, these bands can be attributed to transitions from upper states which are derived from the dissociation products $(X++Y)$ to lower states derived from the products $(X+Y+)$, where $X$ and $Y$ represent the lighter and heavier elements, respectively. The observed band groups for the various combinations have peaks at the following wavelengths: $He-Ne$ (4098, 4238 {\AA}), $He-Ar$ (1426, 1457 {\AA}), $He-Kr$ (1193, 1276 {\AA}), $Ne-Ar$ (2129, 2165, 2203, 2242 {\AA}), $Ne-Kr$ (1645, 1666, 1823, 1833 {\AA}), $Ne-Xe$ (1328, 1342, 1545, 1564 {\AA}) and Ar-Xe (3295, 3458, 5081, 5507 {\AA}). The results of band analyses will be presented for some of these. Part of this paper was presented at the Third International Conference on the Vacuum-UV Radiation Physics, Sept. 1971, Tokyo. H. J. Oskam and H. M. Jongerius, Physica 24, 1092 (1958). H. M. Jongerius, J. L. von Koeveringe and H. J. Oskam, Physica 25, 406 (1959). Von W. Friedl, Zeit. Naturforsch. A14, 848 (1959).