Page:Quarterly Journal of the Geological Society of London, vol. 26.djvu/502

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(2) Dark-coloured clays with Ammonites Martini, Am. Deshayesi, Crioceras, &c. ("Zone of Ammonites Martini." Von Strombeck.)

(3) Dark-blue clays with septaria but with few or no fossils. The Middle Neocomian appears to be represented in Brunswick by the following strata : —

(4) Dark-blue very tenacious clay full of fossils (" Speeton-Thon," " zone of Belemnites brunswicensis" of Von Strombeck)*. It contains the following : —

Belemnites brunswicensis, VonStromb.

Ammonites Nisus, D' Orb.

Pecten cinctus, Sow.

Thracia Phillipsi, Rom.

Avicula Cornueliana, D' Orb. (A. macroptera, Rom.).

Panopaea plicata, Sow.

— neocomiensis, Leym.

Pinna gracilis, Phil.

Terebratula Moutoniana, D'Orb.

Serpula Phillipsi, Rom.

Meyeria ornata, Phil. sp.

(5) Dark-blue clays abounding with Ancyloceras ("zone of Crioceras Emmerici" of Von Strombeck). This bed contains the following : —

Ancyloceras Emmerici, Lev.

— semicinctus? Rom.

Belemnites brunswicensis, Von Stromb.

Serpula Phillipsi, Rom.

Lima longa, Rom.

Terebratula Moutoniana, D' Orb.

Rhynchonella antidichotoma, L" Orb.

(6) Unfossiliferous clays.

(7) Beds of clay full of Exogyra sinuata, Sow. (" zone of Ostrea Couloni, var. aquila " of Von Strombeck).

(8) Unfossiliferous clays.

The total thickness of these clays, representing the Upper and Middle Neocomian, is, in places, according to M. von Strombeck, upwards of 400 feet.

The Lower Neocomian is represented by beds of limestone and sandy marl, containing in places many nodules of iron-ore. The uppermost of these beds abound with specimens of the highly characteristic Toxaster complanatus, Ag. The whole series, which never exceeds 50 feet in thickness, is crowded with fossils, among the most characteristic of which appear to be the Echinoderms, no fewer than 10 species being cited by M. von Strombeck as common to and equally characteristic of these beds and the " Marnes d'Haute-rive " &c. (Lower Neocomian) of the Jura.

The following list will show the nature of the fauna of these beds, which are well seen at Gross Vahlberg, Berklingen, Schandelahe, Schoppenstedt, &c.

Belemnites lateralis, Phil.

Ammonites Astierianus, D' Orb.

— bidichotomus, Leym.

— radiatus, Brug. (A. asper, Merian).

— noricus, Schloth.

Trochus bicinctus, Rom. (T. tricinctus, Rom.).

Pleurotomaria discoidea, Rom.

Ostrea macroptera, Sow.

— subcomplicata, Rom.

— Leunisi, Rom.

— micrantha, Rom.

Exogyra Boussingaulti, D'Orb. (E.

subplicata, Rom.).

— Couloni, Defr. (very abundant).

  • M. von Strombeck, who first noticed these beds, was so struck with the

number of fossils agreeing with those figured in Phillips's Geology of Yorkshire (omitting the supposed (fault forms) that he named this bed the " Speeton- Thon."