The first mention of an Australian Operculate Rugose Coral, was, I believe,. made by the late Rev. W. B. Clarke, F.R.S., in the third edition of his "Sedimentary Formations of New South Wales," wherein the discovery of Calceola is mentioned in the supposed Devonian rocks of Mount Froome, Co. PhiIlip. In the fourth edition of the same publication this locality is again referred to, and Calceola is also said to have been found "along the Yass and Murrumbidgee Rivers." The Clarke specimens are not unfortunately, now extant for reference but previous to the destruction of the collection, the late Prof. de Koninck described from Rock-Flat Creek (probably near Cooma) a Calceolalike Coral, termed by him Rhizophyllum interpunctatum, and it is more than probable that the fossil, formerly referred to by Clarke as Calceola, to which it bears a very strong resemblance on a macroscopic examination only, is a species of Rhizophyllum.