An unusual plant fossil of unknown affinities is reported from the Late Carboniferous of New South Wales.Burdekinia multiseptatagen. et sp. nov. is known from a straplike organ, externally rather featureless, but characterised by a distinctive internal structure of regular transverse sphenopsid-like partitions which form rectangular sections. These sections are filled with a lattice-work of about six parallel rows of small chambers which resembles the internal structure formed by aerenchyma cells in the leaves of the extant marsh plants in the genusTypha.