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Of or pertaining to Devon or Devonshire in England; as, the Devonian rocks, period, or system. Devonian age (Geol.), the age next older than the Carboniferous and later than the Silurian; -- called also the Age of fishes. The various strata of this age compose the Devonian formation or system, and include the old red s…

r containing carbon or coal. Carboniferous age (Geol.), the age immediately following the Devonian, or Age of fishes, and characterized by the vegatation which formed the coal beds. This age embraces three periods, the Subcarboniferous, the Carboniferous, and Permian. See Age of acrogens, under Acrogen. -- Carbonifero…

The closing subdivision of the Devonian age in America. The rocks of this period are well developed in the Catskill mountains, and extend south and west under the Carboniferous formation. See the Diagram under Geology.

A plume-shaped fossil, supposed to be a seaweed, characteristic of the lower Devonian rocks; as, the cauda galli grit. Gauda galli epoch (Geol.), an epoch at the begining of the Devonian age in eastern America, so named from the characteristic gritty sandstone marked with impressions of cauda galli. See the Diagram und…

A genus of fossil ganoid fishes found in the old red sandstone or Devonian formation. The head is large, and protected by a broad shield-shaped helmet prolonged behind into two lateral points.

A subdivision in the upper part of the Devonian system in America, so named from the Chemung River, along which the rocks are well developed. It includes the Portage and Chemung groups or epochs. See the Diagram under Geology.

formerly supposed to be of one formation, but now known to be partly Silurian and partly Devonian.

An extinct genus of Devonian ganoid fishes, having the broad plates about the head studded with berrylike tubercles.

Of or pertaining to the lowest period of the Devonian age.(See the Diagram, under Geology.) The Corniferous period has been so called from the numerous seams of hornstone which characterize the later part of the period, as developed in the State of New York.

A genus of trilobites, of many species, common in the Upper Silurian and Devonian rocks.

A genus of large extinct Devonian ganoid fishes. In some parts of Ohio remains of the Dinichthys are abundant, indicating animals twenty feet in length.

A genus of fossil corals abundant in the Silurian and Devonian rocks, having polygonal cells with perforated walls.

The closing subdivision of the Hamilton period in the American Devonian system; -- so called because the formations of this period crop out in Genesee, New York.

genus of fossil cephalopods, allied to the Ammonites. The earliest forms are found in the Devonian formation, the latest, in the Triassic.

A genus of fossil fishes, found in Devonian and carboniferous strata; -- so named from their round, sculptured spines.

A subdivision of the Devonian system of America; -- so named from Hamilton, Madison Co., New York. It includes the Marcellus, Hamilton, and Genesee epochs or groups. See the Chart of Geology.

A genus of fossil trees of the Devonian and Carboniferous ages, having the exterior marked with scars, mostly in quincunx order, produced by the separation of the leafstalks.

An extensive genus of fossil ferns, of which species have been found from the Devonian to the Triassic formation.

ican Paleozoic system intermediate or translational in character between the Silurian and Devonian ages. See Chart of Geology.

on of geological time during which life is known to have existed, including the Silurian, Devonian, and Carboniferous ages, and also to the life or rocks of those ages. See Chart of Geology.