SUMMARYOLSON, S. L. 1977. The identity of the fossil ducks described from Australia by C. W. De Vis, Emu 77: 127–131.The type material of the nine species of fossil ducks described from Australia by C. W. De Vis was restudied and lectotypes designated for all species based on series. No valid extinct species were represented.Nyroca robustais a synonym ofAnas superciliosa. Nyroca reclusaandAnas elapsaare synonyms ofAythya australis. Nyroca effodiatais a synonym of‘Leucosarcia proevisa’De Vis and is not a duck at all.Anas strenua, Anas gracilipesandNettapus eyrensisare synonyms ofAnas castanea, which species evidently had a wider range in the late Pleistocene than at present.Dendrocygna validipinnisandBiziura exhumataare synonyms ofBiziura lobata, although the Plio-Pleistocene form may have been slightly smaller, in which case it would be known asBiziura lobata validipinnis.