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The two nearest spiral galaxies, M31 and M33, have been extensively studied both at optical as well as at radio wavelengths. Reviews of radio continuum observations are given in van der Kruit and Allen (1976) and in von Kap-herr et al. (1978), respectively. In Table 1 new radio observations in various stages of progress are listed, all of which show — or are expected to show — spiral structure. In this paper the Effelsberg maps at 11 cm of M31 and at 6 cm of M33 are discussed and compared with optical data. Some attention is given to the separation of thermal and nonthermal emission which is essential to any discussion of the origin of the radiation.