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Updated: May 23, 2025
Upper Lias, argillaceous, with Ammonites striatulus. FOREIGN. Keuper beds of Germany. Cassian or Hallstadt beds, with rich marine fauna. BRITISH. Wanting. FOREIGN. Muschelkalk of Germany. BRITISH. Bunter or Lower New Red sandstone of Lancashire and Cheshire. FOREIGN. Bunter-sandstein of Germany. BRITISH. Upper Permian of St. Bees' Head, Cumberland. FOREIGN. Dark-coloured shales of Thuringia.
|Quaternary |Recent Cenozoic | |Pleistocene | |Tertiary |Pliocene |Miocene |Eocene |Cretaceous Mesozoic |Jurassic |Triassic |Permian |Carboniferous |Pennsylvanian | |Mississippian Paleozoic |Devonian |Silurian |Ordovician |Cambrian Algonkian Archean
The periods we have already covered the Cambrian, Ordovician, Silurian, Devonian, Carboniferous, and Permian form the Primary or Palaeozoic Era, to which the earlier Archaean rocks were prefixed as a barren and less interesting introduction. The stretch of time on which we now enter, at the close of the Permian, is the Secondary or Mesozoic Era.
Then comes the Permian period, named, again, from local circumstances, the first investigation of its deposits having taken place in the province of Permia in Russia.
And when we recollect that these things coincide with the extinction of the Ammonites and Belemnites, and the driving of their descendants further south, as well as the rise and triumph of deciduous trees, it is difficult to see any ground for hesitating. But we need not, and must not, imagine a period of cold as severe, prolonged, and general as that of the Permian period.
Upheaval is the one constant and clearly recognisable feature associated with, or preceding, ice-ages. We saw this in the case of the Cambrian, Permian, Eocene, and Pleistocene periods of cold, and may add that there are traces of a rise of mountains before the glaciation of which we find traces in the middle of the Archaean Era.
And it is remarkable that the tortoises, the snakes, and, the more modern forms of crocodile and lizard, and the amphibia and higher insects, are all cainozoic some of them were preceded by more or less transitory representatives, e.g., the Carboniferous Eosaurus and Permian Protosaurus the ancient Labyrinthodons and Urodelas, Chelonians and the amphicaelian crocodiles.
Cold winds blow over it from the new mountains; probably vast regions of it are swept by icy blasts from the glaciated lands. As these conditions advance in the Permian period, the forests wither and shrink. Of the extraordinarily mixed vegetation which we found in the Coal-forests some few types are fitted to meet the severe conditions.
But the limited extent to which these strata are exposed at the surface is not merely owing to their former denudation, but even in a still greater degree to their having been largely covered by the New Red Sandstone, as in Cheshire, and here and there by the Permian strata, as in Durham.
Ramsay agreed with me that it was one of the best published for a long time. The author shows that India has been a continent with enormous fresh-water lakes from the Permian period to the present day. If I remember right he believes in a former connection with South Africa.
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