A review made of the literature covering post-Precambrian volcanism in South Australia has indicated that less well-known, minor, mainly acid to intermediate volcanic rocks of the lower Palaeozoic are separated by a wide time gap from the better known (?) late Tertiary to Recent tholeiite of Kangaroo Island and olivine basalt of Mount Gambier. The early Palaeozoic volcanics comprise late Precambrian to (?) Devonian tuff, trachytes, andesite and rhyodacite of the Gidgealpa region subsurface; Lower Cambrian trachytes seen near Truro in the northern Mount Lofty Ranges; Lower to Middle Cambrian acid tuffaceous rocks of the Flinders Ranges; Middle to Upper Cambrian acid to intermediate tuffaceous rocks of the subsurface in the Gidgealpa region; the Ordovician Kulyong Volcanics (tholeiite) of the north-western part of the State, which display textural characteristics of preservation within a non-orogenic area, in contrast to the other lower Palaeozoic volcanics; and the possibly Ordovician rhyolitic rocks of uncertain relationship seen in the Keith region.