approaching the island everyone was satisfied that the columnar objects were trees, 'except our Philosophers, who still maintained they were basaltes.' The leaves are short, about half an inch long, laterally compressed and slightly spreading and sickle-shaped--sometimes shorter and broader and overlapping--arranged in crowded spirals. The scales of the broadly oval cones are single-seeded, but differ from those of _Araucaria imbricata_ in having the seed exposed on the surface and in the greater breadth and thinner borders of the scales. In both Araucaria and Agathis the nature of the seed-scales constitutes a distinguishing feature. The leaves of _Araucaria imbricata_ differ in form from those of other Conifers. The foliage shoots of _Araucaria excelsa_ and other species, _e.g._ the very closely allied _A. Cookii_ of the New Hebrides and New Caledonia, though not unlike the branches of a Japanese Conifer (_Cryptomeria japonica_), often cultivated in England, afford fairly trustworthy characters for identification purposes. The minute structure of the wood of both Araucaria and Agathis constitutes an important distinguishing feature and enables us to recognise on microscopical examination even a fragment of wood of either of these genera. The small elongated cells or water-conducting elements of the wood of the Araucarieae are characterised by one or two, and occasionally as many as three or four, contiguous rows of pits on their radial walls, and these appear in surface view as flattened circles or polygonal areas. These details have been mentioned in order to show that Araucaria and Agathis are sufficiently distinct in many respects from other Conifers to render their identification in a fossil state comparatively easy, at least much easier than the recognition of the majority of the members of the Coniferae. It would be going too far to state definitely that Araucarieae, as defined by reference to existing species, existed during the Palaeozoic period; on the other hand it would seem in a high degree probable that the vegetation of the Coal age and of the succeeding Permian period included trees in which certain Araucarian characters were clearly foreshadowed. The name Araucarioxylon was formerly applied to petrified wood, obtained from Palaeozoic as well as from later formations, which agrees anatomically with that of Araucaria and Agathis. It has been shown in recent years that much of the Palaeozoic wood of this type of structure belongs to the extinct genus Cordaites, a tree which played a prominent part in the earlier floras. Cordaites affords a good example of a generalised type: in its wood-structure it resembles very closely the existing Araucarieae; its long strap-like leaves are not unlike those of some species of Agathis; its male flowers have often been compared with those of the Maiden Hair tree, _Ginkgo biloba_, and certain anatomical features form connecting links between this Palaeozoic genus and the Cycads.