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Page:Transactions of the Geological Society, 1st series, vol. 2.djvu/190

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180
Mr. Webster on the Strata lying over the Chalk.
Scaphites: a new genus by Mr. Parkinson. See his Organic Remains, vol. 3.
Turrellites, three species.
Trochus.
Madreporæ.

It has been remarked by the French naturalists that in their chalk there is not any univalve shell with a simple and regular spire. In the chalk of this country, univalves, as the trochus, do sometimes occur. They may probably however be rather the fossils of the green sand below the chalk, which have been enveloped in some of the depositions of the chalk formation, or in the chalk marl, for they are frequently accompanied by green earth.

The following Fossils are found in the Chalk in the Environs of Paris

Belemnites Perhaps two species: they appear to be different from those in the compact limestone.
Lenticulites rotulata.
Lituolites nautiloidea.
————— difformis.
Pinna It is not certain that the large fragments of 12 millimetres in thickness and of a fibrous texture, which are found in the chalk belong to this genus. M. Defrance has portions of a hinge which indicate a different genus. Cuv. p. 11.