The original aim of this study was to investigate some of the early Palaeozoic Bryozoa of Australia so as to study the development of skeletal structures in the zoaria and the significance of distribution of species in the different stratigraphic successions. It was found that areas with abundant bryozoan faunas were not readily located; in many areas such as the Yass-Taemas and Tamworth districts, New South Wales, where Silurian and Devonian marine faunas are abundant, Bryozoa were poorly represented. Thus the work became an investigation of areas where Bryozoa were located. The Middle and Upper Ordovician exposures in parts of central-western New South Wales and the Middle and Upper Devonian sequence of the Fitzroy Basin (collected by the field parties of the Bureau of Mineral Resources) contained abundant bryozoan faunas at certain horizons; but they were not distributed continuously through any considerable thickness of succession. Many samples from which Bryozoa are described in the text are isolated occurrences from which two, sometimes three, species have been collected.