the dark argillaceous oolites and blue mottled lias for the yellow crystalline dolomite, is in harmony and keeping with the plants and animals which now, for the first time, sprang into existence. II. THE ORGANIC REMAINS are very abundant, and in both plants and animals there are various new kinds. Of the former are the cycadeæ, allied to the existing pine-apple; also the lilaceæ, and some other undescribed genera. With regard to animals, this has been emphatically called “the age of reptiles,” along with which there are new families of fishes, crustacea, mollusca, and corals. The warm-blooded animals now for the first time appear, of which there are two genera, the _Amphitherium_ and _Phascolotherium_, found in the Stonesfield slate near Oxford, and considered, by analogy of structure, to be allied to the marsupials that inhabit the Australian continent. The same interesting locality has furnished two new genera of insects, the _Prionus Ooliticus_ and _Coccinella Wittsii_; in the lias, of different places, eleven genera and species have been discovered, but of which only wings and fragments have been obtained. A perfect specimen of this order has recently been found, by the Rev. P. B. Brodie, in the upper lias, near Cheltenham, resembling the genus _diplax_; but so shattered in the head, that its precise character cannot be determined. The reptilians supply alike new terrestrial and marine tortoises and turtles—lizards, whose arms and legs were provided with a filmy membrane, like bats, to enable them to fly—amphibious saurians, and water saurians unlike anything now in existence.