The following facts are summarised from the geology of Queensland written by Mr. Daintree, as the result of his investigations, whilst prosecuting the search for new goldfields on behalf of the Queensland Government in the northern portion of their territory, as also from the official reports of the Geologist of Southern Queensland, and other sources. The consideration and history of the different formations will be taken in their sequence of time, as far as the stratified or sedimentary rocks are concerned. The igneous rocks will be described under the various groups of Granitic, Trappean, and Volcanic. _Aqueous_:-- Alluvial (recent). Alluvial, containing extinct faunas. Desert sandstone, Cainozoic. Cretaceous } Oolitic } Mesozoic Carbonaceous } Carboniferous } Palæozoic Devonian } Silurian } _Metamorphic._ Alluvial.--Fresh-water deposits skirt all the present watercourses, but the accumulations are insignificant on the eastern watershed, except near the embouchures of large rivers, such as the Burdekin, Fitzroy, etc. On the shores of the Gulf of Carpentaria, however, and in the south-western portions of the colony, where the watercourses have scarcely any fall, and where in seasons of excessive rain the country is nearly all inundated, fluviatile deposits are very extensive. Though the dense lavas of the Upper Burdekin (volcanic outbursts of a late Tertiary epoch) are traversed by valleys of erosion, in some cases 200 feet deep, and five miles broad, yet very narrow and shallow alluvial deposits skirt the immediate margin of the watercourses draining such valleys. It is only near the mouths of the larger rivers that any extent of alluvium has been deposited, and even these areas are at the present time in seasons of excessive rain, liable to inundation, showing that little upheaval of this portion of Australia has taken place since the last volcanic disturbances terminated. The meteorological or climatic conditions during this period were nearly identical with those of the present time, heavy rains during the summer months causing violent floods, removing seaward the aërial decompositions and denuded materials from year to year. What lapse of time is represented during this period of erosion is a matter of speculation, but it seems certain that the mollusca of the present creeks were also the inhabitants of the waters during the whole period of denudation since the last volcanic eruption.