The discovery by Keilhau in 1827 of Carboniferous fossils in Spitzbergen first called attention to the geological interest of this archipelago. The collections subsequently made by Robert during the voyage of the “Recherche” in 1838, by Loven in 1837, by Drasche in 1872, and by the series of Swedish expeditions under Baron A. E. von Nordenskiöld between 1858 and 1873, proved the occurrence of beds belonging to the Archean, Lower Palæozoic, Devonian, Carboniferous, Triassic, Jurassic, Cretaceous, and Miocene systems. The fossils collected by these explorers are now in the museums of Christiania, Paris, Stockholm, and Vienna; but up till the present the only collections in London are a few specimens of Devonian fish obtained by exchange, and of Carboniferous Brachiopods collected by Mr. Lamont. It was, therefore, part of the work of Sir Martin Conway's expedition to obtain a series of fossils to represent as fully as possible all the successive faunas and floras of this far northern archipelago. Previous work on the geology of Spitzbergen had, moreover, been carried out on the coast, and it was Sir Martin Conway's main object to explore the interior. These two considerations lessened the thoroughness of the geological study of the country and the extent of the collections, for we had to travel long distances to reach rocks of different systems, and transport of heavy geological specimens from the interior was difficult. Nevertheless, considerable collections were made, which, besides serving to represent the Spitzbergen fossils, will probably aid in the more exact correlation of the horizons from which they come, and throw light on the migrations of the faunas.