downtonian stage
1Devonian — For the Celtic language, see Southwestern Brythonic language; for the residents of the English county, see Devon. Devonian Period 416–359.2 million years ago …
2Old Red Sandstone — Stratigraphic range: Late Silurian to earliest Carboniferous Cross section showing quartz and chert pebbles in a sample from central England (scale bar is 10 mm). Type Geological formation …
