Page:Quarterly Journal of the Geological Society of London, vol. 27.djvu/182

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Teredina personata, Lam., occurs in the wood, and traces of a species of Cliona in the shells of the large Ostrea. A few specimens of Pleurotoma have been observed in the upper portion of this group, but fossils are evidently rare.

(2) Argillaceous Sands with Dentalium. — This group (marked D on the Section, fig. 1) consists principally of thinly bedded strata of greenish argillaceous sand more or less mottled and veined with clay. It includes three or four zones of scattered concretional Septaria, and terminates above in a double layer of claystone or tabular Septaria. A layer of fine whitish sand about 5 inches in thickness runs through the centre of the group and forms a marked feature in the cuttings.

The fossils of this group of strata include the following species : —

Ostrea flabellula, Lam. Syndosmya (Tellina) splendens, Sow.

Pinna, sp.

  • Cardium Laytoni, Morris. *Tellina, spec. nov.
  • Cultellus affinis, Sow. — — , sp.
  • Cytherea suessoniensis, Desh. Teredina personata, Lam.
  • Leda substriata, Morr. Aporrhais Sowerbii, Mant.
  • Modiola simplex, Sow. Fusus, sp.

Nucula gracilenta, S. V. Wood. Leiostoma globatum, Desh.

—, sp. Natica labellata, Lam.

—striatella, S. V. Wood. — —, var.

Panopaea corrugata, Sow. Pleurotoma, sp.

Pholadomya virgulosa, Sow. Rostellaria lucida, Sow.

—margaritacea, Sow. Trophon tuberosum, Sow.

  • Pholas, spec. nov. (allied to *Dentalium, spec. nov.

Levesquei). * — —, Var.

  • Solen (large species). *Thenops scyllariformis, Bell.
  • — sp. *Bryozoon.

These fossils occur dispersed throughout the sands. The specimens of Panopoea, Pholas, and Pholadomya occur in the position in which they lived, and with their valves united. The species marked with a star are restricted to this group ; the rest range higher.

(3) Sands with Lingula. — This group of sands deserves special notice on account of the number and variety of its fossils. It includes the following beds : —

E. Greenish sands with thin layers of clay 5 feet.

F. One or more thin layers of greenish chloritous sand, crowded with fossils, and resting in places on a thin layer of clay 1 to 3 inches.

G. Greenish sand, finely stratified, with one or more layers of shells , 3 feet.

The abundance of green matter in these sands is very conspicuous.

Concretions of shell-rock many feet in length occur along the line of sand and shells at F, sometimes including and sometimes resting on, or appearing to be suspended from, the layer of shells. This shell rock, which has very much the appearance of Bognor rock, is so hard as to require blasting.

More than eighty species of fossils, several of which are new to the English Eocene strata, have been obtained from this group of strata. A few of these, such as Lingula tenuis, Sow., and Panopoea