The Fossil Plants of the Devonian and Upper Silurian Formations of Canada, Parts 1-2Dawson Bros., 1871 - 142 pages |
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Acadian Acadian Geology acrogens acuminate Alethopteris allied Annularia appear areoles Arthrostigma Asterophyllites axis beds belong Bipinnate branches branchlets Brunswick Calamites Calamodendron Canada Cardiocarpum Caulopteris cells coal Cordaites Cyclopteris Cyclostigma Dadoxylon decurrent Devonian period diameter distinct Erian flora ferns fibres flattened forms fossil plants fragments fronds fructification Gaspé genera genus Goeppert Hartt's collections Hymenophyllites inch indicate Jacksoni John leaf leaves LEGGO Lepidodendron Lepidophloios Lepreau limestone Lith Montreal Longitudinal Lower Carboniferous Lower Devonian Lycopodites margin medullary rays Middle Devonian midrib Nematoxylon Neuropteris oblique obtuse occur oval Pecopteris Perry petiole pinna pinnæ Pinnularia pinnules pith portion enlarged preserved probably Prof Prototaxites Psilophyton rachis referred represented resemble rhizomata ribs robustius rocks roots scalariform scars Schimper shales showing Sigillaria similar slender species specific types specimens Sphenopteris spore-cases stems Sternbergia Stigmaria strobiles structure surface thick transverse tree ferns trunks Upper Devonian Upper Silurian venation whorls wood-cells woody XVII XVIII York
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Page 10 - Artisia (Sterubergia) type; wood cells very large, with three to five rows of contiguous alternate hexagonal areoles with oval pores; medullary rays with one to three series of cells and as many as fourteen rows of cells superimposed on each other (Dawson.) Middle Erian (Devonian) formation, of Canada.
Page 8 - Division" 4. Great difficulties have been experienced in the classification of the European Devonian, and the uncertainties thus arising have tended to throw doubt on the results obtained in America in circumstances in which such difficulties do not occur. These reasons are, I think, sufficient to warrant me in holding the great Erie Division of the New York geologists as the typical representative of the rocks deposited between the close of the Upper Silurian and the beginning of the Carboniferous...
Page 79 - We see in the Laurentian series beds and veins of metallic sulphurets, precisely as in more recent formations, and the extensive beds of iron ore, hundreds of feet thick, which abound in that ancient system, correspond not only to great volumes of strata deprived of that metal, but, as we may suppose, to organic matters, which but for the then great diffusion of...
Page 47 - ... are evidently injudicious. Neuropteris polymorpha, Dawson (Fig. 192, C). Pinnate or bipinnate. Rachis or secondary rachis irregularly striate. Pinnules varying from round to oblong, unequally cordate at base, varying from obtuse to acute. Terminal leaflet ovate, acute, angulated or lobed. Midrib delicate, evanescent. Nervures slightly arcuate, at acute angles with the midrib. This fern is very abundant in the shales near Carlton, at St John. At first sight it appears to constitute several species,...
Page 52 - Bipinnate. Pinnules rather loosely placed on the secondary rachis, but connected by their decurrent lower sides, which form a sort of margin to the rachis. Midrib of each pinnule springing from its upper margin and proceeding obliquely to the middle. Nerves very fine and once-forked. Terminal leaflet broad. This fern so closely resembles Pecopteris Serlii and P. lonchitica that I should have been disposed to refer it to one or other of these species but for the characters above stated, which appear...
Page 35 - ... minute punctate scars. Young branches circinate ; rhizomata cylindrical, covered with hairs or ramenta, and having circular areoles irregularly disposed, giving origin to slender cylindrical rootlets. Internal structure — an axis of scalariform vessels, surrounded by a cylinder of parenchymatous cells, and by an outer cylinder of elongated woody cells. Fructification consisting of naked oval sporecases, borne usually in pairs on slender, curved pedicels, either lateral or terminal.
Page 27 - Stems simple, elongated, attaining a diameter of half an inch, obscurely striated ; bearing on the nodes whorls of round or oval scales, or flattened nutlets, which at the ends of the stems are crowded into a sort of spike, while on other parts of the stems the nodes are sometimes an inch apart.
Page 43 - Nat." vol. vi. p. 173, fig. 9. " Frond bipinnate ; rachis stout and longitudinally furrowed; pinnae alternate; pinules obliquely obovate, imbricate, narrowed at the base, and apparently decurrent on the petiole; nerves nearly parallel, dichotomous ; terminal leaflet large, broadly obovate or lobed.