Coralline Crag. It is on the side of this old yard, and therefore immediately above the bed with Cardita &c., that the Coralline Crag rises in an old cliff well described by Sir Charles Lyell[1], and to which I shall have occasion to refer again. The lower part of this cliff consists of light-coloured sands (e), with a few Bryozoa and a good many small shells; while the upper part (part of f) is composed in great part of comminuted shells. No higher bed is seen here; but on the other side of the hill, and at a distance of 400 feet west of this pit, is an old quarry, which, when I first visited it in 1836, had recently been extensively worked for rubble to form the river-wall. In the lower part of this pit (fig. 2) the bed of sand e, just referred to in the Bullock-yard pit, is well exposed. It is 12 feet thick, and consists of a light yellow sand, with a few shells, mostly small or young individuals, with a number of Bryozoa in a fine state of preservation and mostly in the position in which they lived. In some places these Bryozoa are very numerous, and arranged in regular but not continuous bands, like flints in the Chalk. The prevailing species are Cellepora coronoporus, Eschara porosa, and other species of Cellepora and Eschara, a species of Ceriopora, and another large branching species. Many of these are in the most beautiful state of preservation and perfectly uninjured. They are now, however, best seen in a small section between the large pit or quarry and the cottages at the entrance to the Bullock-yard.
| Fig. 2.—Section in old Quarry, Sutton. Top of hill overlooking the Deben. (See F, Map and Sections, Pl. VI.) | |
|
Surface soil. |
| Dark ferruginous beds of Bryozoa, mostly in fragments, some entire, with a few shells in the same state. White soft calcareous veins descend through these beds from the top. 11 feet. | |
| Fine sand and grit, comminuted shells, numerous small perfect shells, and some Bryozoa. 6 feet. | |
| Uniform fine compact sand, with small shells and Bryozoa in the position of growth. 4 feet. | |
Overlying these sands with undisturbed Bryozoa is a bed, f, from 5 to 8 feet thick, consisting of comminuted shells with seams of oblique lamination, containing a few Bryozoa, and with a considerable number of shells, also mostly small or young individuals, in a good state of preservation. Intercalated in this bed are several finely laminated indurated irregular seams of yellow marl or limestone, containing small shells. Foraminifera, and some rare species
- ↑ Op. cit.
