Graptolites definition of Graptolites in the Free Online Encyclopedia.

graptolites [′grap·tə‚līts]

(paleontology)

Graptolites

(Graptolithina), a subphylum of extinct marine colonial animals of phylum Hemichordata.

Graptolites are known from the Cambrian to the Carboniferous periods; they were most common in the Ordovi-cian. Silurian, and lower Devonian periods. The skeletons of graptolites consisted of chitinous branches formed from little compartments in which the zooids lived. Graptolites were either benthic or planktonic. Planktonic graptolites had a swim bladder filled with gas released by the zooids as a product of their vital processes. There were two classes: Stereostolonata, with hard stolons and functionally varied compartments, and Graptoloidea, without stolons and with uniform compartments. Graptolites are of great importance as index fossils.

REFERENCE

Obut, A. M. “Tip Hemichordata (Gemikhordovye): Podtip Graptolithina (Graptolity).” In Osnovy paleontologii: Iglokozhie, gemikhordovye, pogonofory i shchetinkocheliustnve. Moscow, 1964.

A. M. OBUT

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No references found	Graptolites are generally very rare in carbonate rocks, yet, may be rather common in some marly intervals and help to improve stratigraphical correlations. Baltic stratigraphical conferences foster geological cooperation and ... by Kaljo, Dimitri; Hints, Olle / Estonian Journal of Earth Sciences Distribution of graptoloids in the Ordovician carbonate rocks of the East Baltic area // Graptolites and Stratigraphy / D. Age of Estonian kukersite oil shale--middle or late Ordovician? by Hints, O.; Nolvak, J.; Viira, V. / Oil Shale This level is close to the first appearance of Dicellograptus, however, graptolites are extremely rare or absent in the main part of the Uhaku Stage. Ordovician timescale in Estonia: recent developments/Eesti ... by Nolvak, Jaak; Hints, Olle; Mannik, Peep / Proceedings of the Estonian Academy of Sciences: Geology	Graphite-Gas Reactor graphite-moderated reactor Graphite-Water Reactor graphitic carbon graphitic corrosion graphitic steel Graphitization graphitizing Graphological Identification Graphology graphoscope Graphs, Theory of grapnel Grapow, Hermann Grappelli Grappelli, Stéphane grappier cement grapple grapple dredger grapple hook grappler grappling iron Grapsidae graptolite graptolite shale Graptolites Graptolithina Graptoloidea Graptozoa GRAS Gras, Felix Gras, Félix graser Grashchenkov, Nikolai Grashchenkov, Nikolai Ivanovich Grashi, Ashot Grashi, Ashot Bagdasarovich Grashof formula Grashof number Grasmere Grasmere Sports grasp GRASP/Ada GRASPIN grass grass cloth grass crops Grass Family Grass Fattening of Livestock Grass Goby grass hockey	grappling grappling grappling Grappling gun Grappling hold grappling hook grappling hook grappling hooks grappling iron grappling iron grappling iron grappling iron grappling iron grappling irons Grappling position Grappling Range Instructional Procedures for Police Grappling tongs Graps Graps Graps Graps Graps Grapsid Crabs Grapsidae Grapsoid Graptolita Graptolita graptolite graptolite graptolite shale Graptolites Graptolithina Graptolithina Graptolitic Graptoloidea Graptolyte Graptolyte graptomancy Graptopetalum paraguayense Graptopetalum paraguayense Graptophyllum Graptophyllum pictum Graptozoa GRAPWG grapy grapy grapy GRAR GRARA GRARE GRARFOTS GRARL GRAS GRAS GRAS GRAS Gras Becks Und Zärtlichkeit Gras, Felix Gras, Félix GRASA Grasanòbol

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Graptolites are generally very rare in carbonate rocks, yet, may be rather common in some marly intervals and help to improve stratigraphical correlations.

Baltic stratigraphical conferences foster geological cooperation and ... by Kaljo, Dimitri; Hints, Olle / Estonian Journal of Earth Sciences

Distribution of graptoloids in the Ordovician carbonate rocks of the East Baltic area // Graptolites and Stratigraphy / D.

Age of Estonian kukersite oil shale--middle or late Ordovician? by Hints, O.; Nolvak, J.; Viira, V. / Oil Shale

This level is close to the first appearance of Dicellograptus, however, graptolites are extremely rare or absent in the main part of the Uhaku Stage.

Ordovician timescale in Estonia: recent developments/Eesti ... by Nolvak, Jaak; Hints, Olle; Mannik, Peep / Proceedings of the Estonian Academy of Sciences: Geology