The Geological History of Plants

abundant Acrogens Algæ allied America animal appear Archæopteris arctic areoles bark beds belong bituminous branches Brongniart Calamites Canada carbon Carboniferous Caulopteris cellular character clay climate coal coal-formation conifers Cordaites cycads Dadoxylon Dawson deposits described Devonian diameter dicotyledonous Eocene Europe exogenous fact ferns flora formation forms fossil fossil plants fronds fructification fruit Gaspé genera genus Geological Society graphite Greenland gymnospermous Heer hemisphere Illustrations Journal known land land-plants Laramie Laurentian leaf-bases leaf-scars leaves Lepidodendron Lepidophloios Lesquereux limestone Lower Carboniferous Lycopods macrospores matter medullary rays Mesozoic Miocene modern Nematophyton northern Nova Scotia occur outer Palæozoic period Permian pines pinnules pith present preserved probably Prof Psilophyton referred remarkable resemble Rhizocarps rocks sandstones scalariform scars Sequoia shales Sigillaria Silurian similar species specimens Sphenophyllum Sporangites spore-cases spores sporocarps stems Sternbergia structure surface Tertiary thick tion tissue tree-ferns trees trunks types Upper Cretaceous vascular vegetable wood woody