Page:The Geologist, volume 5.djvu/152

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128
THE GEOLOGIST.
5. Stiff Blue Clay
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
5 feet
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
With Ammonites Henleyi, Perna ventricosa, and Myacites.
6. Hard stiff Blue Clay
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
12—14ft.
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With Ammonites fimbriatus, A. margaritatus, A. Henleyi, Perna ventricosa, and small Pentacrinite.
7. irregular band of limestone, generally formed of a mass of shells
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Unicardium cardioides, Cardinea concinna, Myacites tumidus (?), Modiola scalprum, Grervillia lævis, Perna ventricosa, Lima (small), Ostrea (small), Pecten Sublævis, Plagiostoma Hermanni, Terebratula numismalis, Rhynchonella furcillata, R. concinna, R. subconcinna, Pentacrinus.

The upper shelly bed (No. 2) undulates; the distance between the crest and the trough of the wave being about a hundred yards, and the depth of the trough about six feet. This is very much stained with oxide of iron.

The clayey beds Nos. 3, 5, 6, have fossiliferous concretionary nodules, and are all very similar; they contain but few fossils, and those mostly of the same species. Bed No. 7 is also stained with iron, but not so much so as bed No. 2. It is very irregular as to its composition; the stony bed being often interrupted by coarse concretionary masses at some distance from each other. This bed I also found at Oddington, four miles from the railway-cutting; and there it is only just beneath the surface-soil, so that there must have been considerable denudation.

I should think that the Upper Lias Clay is much thicker in this locality and at Chipping-Norton than is generally supposed. Mr. Bliss, the owner of the factory there, told me that he bored 500 feet without getting through the clay. This is where it crops from beneath the Inferior Oolite.

Though the beds above described may possibly belong to the Middle Lias, yet I think there is much evidence to the contrary, such as the close contiguity of the Inferior Oolite, especially the "passage-sands," with the ferruginous ammonite-bed. At Oddington, about three miles from the cutting, these sands rest directly on bed No. 7 of the section.


TRAILS, TRACKS, AND SURFACE-MARKINGS.

By T. Rupert Jones, F.G.S.

Geologizing, with some friends, on the south coast of the Isle of Wight, a few summers since (1859), we noticed some puddles of rain-water in the clay talus of the Wealden Cliffs near Brook Point, and observed that, like other such surfaces, the partially dried clay beds of the diminished pools showed rain-prints, foot-tracks, trails, and the rings of broken bubbles. Amongst these various markings are convex trail-like lines (fig. 1), which at first appeared difficult to account