| Upper term. | Epilimnic or upper freshwater formation—the uppermost of all the stratified deposits near Paris; consisting chiefly of siliceous limestone, or burr stone, marl, and marly sands.
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Upper marine formation—consisting of sandstone, generally white, or partially reddened or ochraceous, and but slightly aggregated, except at Fontainbleau.
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| Lower term. | Palæotherian freshwater formation—characterised near Paris by its ossiferous gypsum and marls, siliceous limestones, &c.
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Lower marine formation—consisting principally of limestone (calcaire grossier) of various degrees of coarseness, with laminated flint, marls both calcareous and argillaceous, green sands
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Plastic clay group—an irregular mass of deposits varying with locality, in places yielding plastic clay and sands; in other situations, lignites or pebble beds.
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There is no trace in the basin of Paris of the shelly and gravelly deposits (falun coquillier) of Touraine, which M. J. Desnoyers compares to the English crag, and considers to be more recent than the epilimnic group of the Parisian basin.
It is obvious that the agreement between the Parisian and English tertiaries is merely in the great features of succession: the lower marine formation in England is principally clay in France, limestone: gypsum abounds in the palæotherian freshwater beds of France, but not in England. Yet the basin of the Seine, and that of Hampshire, were connected with the same sea, and subject to very similar successions of marine and fluviatile agencies. The difference of deposits is due to the different materials transported in the currents of the sea.
In the south of France the tertiary deposits of the large basin of the Garonne, contain shells like those of Touraine; the beds of Narbonne and Montpellier more resemble the Parisian series. In M. Dufrenoy's recent memoir, he arranges the tertiaries of the south of France
