Page:Quarterly Journal of the Geological Society of London, vol. 26.djvu/497

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contains an eminently Aptian or Upper-Neocomian fauna, including Ammonites Deshayesi, Leym., A. Martini, D'Orb., Am. Nisus, D'Orb., &c. ; while the lower portion contains a fauna which is as unmistakably that of the Middle Neocomian, comprising Pecten cinctus, Sow. (of large size and in great abundance), Ammonites clypeiformis, D'Orb., Thracia Phillipsi, Rom., Serpula Phillipsi, Rom., Meyeria ornata, Phil, sp., and Terebratula hippopus, Rom.

The Upper Neocomian beds do not appear to be generally well exposed in this country, and only a small fauna has, as yet, been recorded from them ; the Middle Neocomian, on the other hand, is admirably exhibited at a number of different points, and has yielded a large and very interesting series of fossils.

A few years ago a canal, which passed along the base of the Lindener Berg, about a mile from the town of Hanover, very well exposed the Middle Neocomian beds of the Hilsthon, the fossils of which were collected by M. Witte. Among these fossils I was able to identify the following : —

Ammonites clypeiformis, D' Orb.

— marginatus, Phil.

— rotula, Sow.

— Nisus, D'Orb.

Pecten cinctus, Sow.

Pholadomya alternans, Rom.

Lima (several well - known Speeton forms).

Thracia Phillipsi, Rom. (very large).

Terebratula hippopus, Rom.

Meyeria ornata, Phil., sp. (very abundant).

To the south-west of the town of Hanover, along the northern foot of the Deister, the lower beds of the Hilsthon are again well exposed. They rest directly upon the "Walderthon," and consist of greyish-blue clays (from 60 to 70 feet thick), full of septaria of a greyish-brown colour, and nodules of pyrites. At Bredenbeck, in this district, the following large and interesting fauna has been found : —

Belemnites lateralis, Phil.

Ammonites concinnus, Phil.

— Phillipsi, Rom. (?).

— multiplicatus, Rom.

— marginatus, Phil.

— nucleus, Phil. (?)

— noricus, Schloth.

— curvinodus, Phil. (?)

— radiatus, Brug. (A. asper, Merian).

— Gervilianus, D' Orb.

Ancyloceras (Crioceras)-Emmerici, Lev.

Auricula striata, Rom.

Panopaea plicata, Sow.

Pleuromya solenoides, Rom.

Thracia Phillipsi, Rom.

Cucullaea Schusteri, Rom.

Pholas constricta, Rom.

Modiola pulcherrima, Rom.

Avicula pectinata, Sow.

Pecten cinctus, Sow.

— orbicularis, Sow. (P. laminosus, Munst.).

— striato-punctatus, Rom.

Palaemon (?) dentatus, Rom.

Meyeria ornata, Phil. sp.

Pollicipes radiatus, Rom.

Serpula quinquecarinata, Rom.

— antiquata, Rom.

Southwards from the Deister the same beds, under somewhat different conditions, are again exposed in the Osterwald. We find these blue clays of the usual character, containing the following fossils : —

Ammonites clypeiformis, D'Orb.

Modiola rugosa, Rom.

Pholas constricta, Rom.

Pholadomya alternaus, Rom.

Lyonsia (?) elongata, Reuss.