Graptolite

Definitions

  • Webster's Revised Unabridged Dictionary
    • n Graptolite (Paleon) One of numerous species of slender and delicate fossils, of the genus Graptolites and allied genera, found in the Silurian rocks. They belong to an extinct group (Graptolithina) supposed to be hydroids.
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Century Dictionary and Cyclopedia
    • n graptolite One of the Graptolithidœ, Graptolithina, or Rhabdophora; a specimen or a species of Paleozoic cœlenterate organisms, commonly supposed to be hydrozoans, resembling the living sertularians in having a horny polypary, and in having the separate zoöids protected by little horny cups, all springing from a common cœnosarc, but differing in that they were not fixed to any solid object, but were permanently free. Graptolites usually appear as impressions on hard shales of the Silurian strata, presenting the appearance of fossil pens, whence the name. Also graptolith.
    • graptolite Same as graptolitic: as, a graptolite schist.
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Chambers's Twentieth Century Dictionary
    • n Graptolite grap′to-līt one of a group of fossil hydrozoa, having simple or branched polyparies, usually strengthened by a horny-like rod—the 'solid axis.'
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Etymology

Webster's Revised Unabridged Dictionary
NL, Graptolithus, from Gr. is engraved, written (gra`fein to write) + stone
Chambers's Twentieth Century Dictionary
Gr. graptosgraphein, to write, lithos, a stone.

Usage

In literature:

A genus of Graptolites.
"The Ancient Life History of the Earth" by Henry Alleyne Nicholson
For there is not any representation to-day of such races as Graptolites and Trilobites.
"The Outline of Science, Vol. 1 (of 4)" by J. Arthur Thomson
The strata consist of greywackes, flags and shales with seams and zones of graptolite shale which yield fossils sparingly.
"Encyclopaedia Britannica, 11th Edition, Volume 6, Slice 1" by Various
These consist of greywackes, flags and shales with bands of dark graptolite shales, the finer sediments being often well cleaved.
"Encyclopaedia Britannica, 11th Edition, Volume 8, Slice 8" by Various
These Graptolites are specially characteristic of the Upper Cambrian and Lower Silurian.
"The Chain of Life in Geological Time" by Sir J. William Dawson
He described also the graptolites of the local Silurian strata; and the flora of the Coal-formation of Altai and Nebraska.
"Encyclopaedia Britannica, 11th Edition, Volume 11, Slice 5" by Various
In the Silurian system, for example, the graptolites have been shown by C. Lapworth to furnish a useful basis for zonal subdivisions.
"Encyclopaedia Britannica, 11th Edition, Volume 11, Slice 6" by Various
The Graptolite polyparies vary considerably in size: the majority range from 1 in.
"Encyclopaedia Britannica, 11th Edition, Volume 12, Slice 3" by Various
A typical graptolite consists of an axis bearing a series of tooth-like projections, like a saw.
"Encyclopaedia Britannica, 11th Edition, Volume 14, Slice 2" by Various
Graptolites occur but rarely in the Upper Cambrian.
"The Elements of Geology" by William Harmon Norton
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