Page:Quarterly Journal of the Geological Society of London, vol. 25.djvu/331

 Eurypterus- zone at Stoke Edith, At Ledbury, according to Mr. Lightbody, there is a thickness of 300 feet between the Downton Sandstone and the passage-beds. At Stoke I could find no trace of the bone-bed, though it appears at Hagley, not far off, and at other places surrounding the Woolhope elevation.

March 24, 1869.

The Rev. Samuel Norwood, B.A., Head Master of the Royal Grammar School, Whalley, Lancashire, was elected a Fellow of the Society.

The following communications were read : —

1. The Cretaceous Strata of England and the North of France compared with those of the West, South- West, and South of France, and the North of Africa. By Prof. Henri Coquand, Marseilles.

[Translated and communicated by J. W. Flower, Esq., F.G.S.]

English geologists may fairly claim the honour of having established in the Cretaceous formation the great divisions which are now generally received, and which find on the European continent their direct application to the strata of the same period. This is more especially true as regards the basin of the Seine, which is in fact but an appendage of that of England.

When, however, we leave the valley of the Seine and approach the Departments of the west of France, we find that the divisions previously recognized become altogether insufficient. For example, between the first beds with Inoceramus labiatus (the base of the Lower Chalk) and the highest layers of the chalk marl (with Ammonites Mantelli), some important beds of sandstone and limestone, characterized by Ostrea biauriculata, Lamk., intervene. These beds are known by the name of the Gres du Mans, and they seem to be wanting in England, as also in the north of France.

If from the Anglo -Parisian basin we pass to that of the Pyrenees, of which the Departments of the two Charentes and the Dordogne constitute the northern limits, at least in a geological point of view, we meet with still more important modifications. Thus, the Gres du Mans are here more highly developed, and force themselves upon the notice of the palaeontologist on account of the great abundance of Rudistes which they contain, such as Sphoerulites foliaceus, Lamk., Caprina adversa, C. M. D'Orb., Caprina Fleuriausii, Monopleura polyconilites, &c. Above this layer, of which the Oyster-beds (Ostrea biauriculata, Lamk., and Ostrea flabella, D'Orb.) invariably form one of the constituents, are the marly beds of the Lower Chalk with Inoceramus labiatus, a stratum which in England and in Picardy comprises in its upper portion the layers with Ostrea acuti-

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