The Fossil Flora of Great Britain: Or, Figures and Descriptions of the Vegetable Remains Found in a Fossil State in this Country, Volumen1

Portada
J. Ridgway, 1833 - 462 páginas
 

Comentarios de la gente - Escribir un comentario

No encontramos ningún comentario en los lugares habituales.

Otras ediciones - Ver todas

Términos y frases comunes

Pasajes populares

Página xiv - Coniferae nor any other dicotyledonous plants existed in the first geological age of land plants, still the theory of progressive development would be untenable ; because it would be necessary to show that Monocotyledons are inferior in dignity, or, to use a more intelligible expression, are less perfectly formed than Dicotyledons. So far is this from being the case, that if the exact equality of the two classes were not admitted, it would be a question whether Monocotyledons are not the more highly...
Página 94 - ... or root growing in a direction nearly horizontal in the soft mud at the bottom of freshwater lakes or seas, without branches, but sending out fibres from all sides; that it was furnished in the centre with a pith of a structure different from the surrounding wood or cellular substance, more dense and distinct at the older end of the plant...
Página 90 - Not unfrequently, the flattened side turns in so as to form a groove. The surface is marked in quincuncial order with pustules, or rather depressed areolae, with a rising in the middle, in the centre of which rising a minute speck is often observable. From different modes and degrees of compression, and, probably, from different states of the original vegetable, these areolae assume very different appearances, sometimes running into indistinct rimae, like the bark of an aged willow, sometimes, as...
Página 12 - It is the beds of shale, or argillaceous schistus, which afford the most abundant supply of these curious relics of a former World ; the fine particles of which they are composed having sealed up and retained in wonderful perfection, and beauty, the most delicate forms of the vegetable organic structure.
Página 12 - ... and causing it to separate and fall, when by the operation of the miner the coal which supported it is removed. After an extensive fall of this kind has taken place, it is a curious sight to see the...
Página vii - ... from the parts of the plant on which it grew, so that no man can tell how to collect the fragments that remain into a perfect whole. For it must be remembered, that it is not in Botany as in Zoology, where a skilful anatomist has no difficulty in combining the scattered bones of a broken skeleton. In Botany, on the contrary, the component parts of both foliage and fructification are often so much alike in outline, which is all that the Fossil Botanist can judge from, as .to indicate almost nothing...
Página xiv - But supposing," continue the same authors, " that it could be demonstrated, that neither Coniferae nor any other dicotyledonous plants existed in the first geological age of land plants, still the theory of progressive development would be untenable ; because it would be necessary to show that Monocotyledons are inferior in dignity, or, to use a more intelligible expression, are less perfectly formed than Dicotyledons. So far is this from being the case, that if the exact equality of the two classes...
Página 171 - Polyporites, consider as very doubtful its reference to the vegetable kingdom. Mr. Bowman, the discoverer to whom the species is dedicated as P. Bowmanni, remarks, that one of his specimens might be taken for the scale of a fish or of some great Saurian. Since that time no kind of remains referable to Fungi has been seen in the coal, except one specimen found in the Anthracite measures near Pottsville, Pa. It is apparently identical with the English species, and does not afford any more light upon...
Página xli - ... than the tortuous depressed spaces that separate them. Genus V. — Sphenopteris. Leaves bi-tripinnatifid ; leaflets contracted at the base, not adherent to the rachis, lobed; the lower lobes largest, diverging, somewhat palmate ; veins bipinnate, radiating, as it were, from the base. Genus VI. — Neuropteris. Leaves bipinnate, or rarely pinnate ; leaflets usually somewhat cordate at the base, neither adhering to each other nor to the rachis, by their whole base, only by the middle portion of...

Información bibliográfica