|
|
|
|
|
|
|
|
Lower
Devonian
|
Middle Devonian |
Lower
Devonian
|
Lower
Devonian
|
Scotland |
Scotland |
Scotland |
Scotland |
|
|
|
|
|
|
|
|
Middle
Devonian |
Middle
Silurian |
Upper
Silurian |
Upper
Silurian |
Scotland |
Scotland |
Scotland |
Scotland |
|
|
|
|
|
|
|
|
Upper
Silurian |
Pennsylvanian |
Middle
Devonian |
Upper
Silurian |
Scotland |
Kansas |
Scotland |
Scotland |
|
|
|
|
|
|
|
|
Upper
Silurian |
Upper
Silurian |
Carboniferous |
Upper
Devonian |
Scotland |
Scotland |
Siberia |
Ukraine |
|
|
|
|
|
|
|
|
Middle
Devonian |
Upper
Devonian |
Middle
Devonian |
Upper
Devonian |
Scotland |
Quebec,
Canada |
Scotland |
Podolia,
Ukraine |
|
|
|
|
|
|
|
|
Lower
Devonian |
Early Permian |
Carboniferous |
Carboniferous |
Caithness,
Scotland |
Pflaz,
Germany |
Bear
Gulch, Montana |
Siberia |
|
|
|
|
|
|
Palaeobergia
microlepis |
|
Lower
Devonian |
Mississippian |
Carboniferous |
Permian |
Tynet
Burn, Scotland |
Bear
Gulch Limestone, Montana |
Siberia |
Jeckenbach
Formation, Germany |
|
|
|
|
|
|
|
|
Middle
Devonian |
Mississippian
|
Mississippian
|
Devonian |
Scotland |
Bear
Gulch Limestone, Montana |
Bear
Gulch Limestone, Montana |
New
South Wales, Australia |
|
|
|
|
|
|
|
|
|
Mississippian
|
Mississippian |
Mississippian |
Mississippian |
Bear
Gulch Limestone, Montana
|
Bear
Gulch Limestone, Montana |
Bear
Gulch Limestone, Montana |
Albert
Shale, New Brunswick,
Canada |
|
|
|
|
|
|
Scaumenacia curta |
|
Mississippian |
Carboniferous |
Upper Devonian |
Mississippian |
Bear
Gulch Limestone, Montana |
Siberia |
Escumiac Bay, Quebec, Canada |
Bear
Gulch Limestone, Montana |
|
|
|
|
|
|
|
|
Mississippian |
Lower Devonian |
Permian |
Pennsylvanian |
Bear
Gulch Limestone, Montana |
Powys, Wales, United Kingdom |
Marl Slate,
England |
Johnson
County, Missouri |
|
|
|
|
|
|
|
|
Middle
Devonian |
Middle Devonian |
Middle
Devonian
|
Silurian |
New
South Wales, Australia |
Caithness, Scotland |
Caithness,
Scotland
|
Ayrshire,
Scotland |
|
|
|
|
|
|
|
|
Carboniferous |
Mississippian |
Lower Devonian |
Upper
Devonian
|
Kyzykchul
Formation, Western Siberia |
Bear
Gulch Limestone, Montana |
Turin Hill, Forfar, Scotland |
Bergisch-Gladbach,
Germany
|
|
|
|
|
|
|
|
|
Silurian |
|
|
|
Island of Oesel, Estonia |
|
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|