The identification of the Rhætic Formation in Britain, previously discovered to be intercalated between the Keuper Marls and Lower Lias Shales in Germany, we owe to the labours of Dr. Wright, F.G.S., and Mr. Charles Moore, F.G.S., In the year 1860, the former published an account of the strata beneath the Lias, characterized by the occurrence of Avicula contorta; the latter, in the following year, showing in a most valuable paper the true relation of the sandstones, shales, and limestones to the White Lias above and the Keuper below, added upwards of twenty-eight new species to the list of British Fossils.