Page:Quarterly Journal of the Geological Society of London, vol. 27.djvu/620

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laminated sandy clay, at the base of which freshwater shells are found. The shells are only in occasional patches, and consist of Unio pictorum, Cyclas cornea, and Bythinia tentaculata* .

As we approach Pakefield the bed of shingle, which rests on the clay (3) becomes ferruginous, and contains pebbles of clay derived from the Chillesford Clay. A considerable number of mammalian remains'(Elephant?, Rhinoceros, Deer, Ox, and Horse, the same apparently as in the Forest-bed of Norfolk) have been found in this bed.

Besides the common occurrence in this cliff of rootlets passing from the base of the shingle into the underlying clay to a depth of 4 or 5 feet, the trunk of a tree, 20 feet long, was found some years since on the surface of the clay-bed (3), and nearer to Pakefield the stool of a large tree was found in situ, as at Hasborough.

Nearer to Pakefield the Chillesford Clay is entirely broken up, and a bed composed of sand, flint-pebbles, and pebbles of Chillesford clay takes its place, while the " Westleton sand and shingle " is immediately overlain by the upper division of the Boulder-clay.

At Corton, to the north of Lowestoft, the Forest-bed appears again for a short distance at the foot of the cliff, with the Lower Boulder-clay immediately above it, whilst the Westleton beds are wanting. They are largely developed inland, however, and are worked on the west side of the Somerleyton brick-pit, and at several pits N.W. of Lowestoft.

From the cliffs at Corton, where we lose the Forest-bed, to the cliffs at Hasborough, where it again crops out at the foot of the cliff, is a distance of 24 miles. The Crag-beds beneath it there (if they exist) are not exposed ; but in the series above it we find the same order of succession as at Southwold and Kessingland. The Forest-bed along this coast appears to exist, as between Pakefield and Kessingland, under two forms : — the one a local freshwater deposit of grey and carbonaceous clay, containing the remains of mammalia, insects, plants, and freshwater shells ; and the other of trees, rooted sometimes in this bed and sometimes in the Chillesford Clay beneath it. It is not often the latter is seen. It appears, however, on the shore at low tide at Pauling. The Forest-bed itself has been bored into at Hasborough by Mr. Gunn to the depth of 14 feet, without reaching its base. From this point to Trimlingham none of the beds under this level are visible ; but the Westleton beds are well exhibited at various places, as, for example, at the cliff north of Bacton Gap (fig. 35 ; see also coast-section, Pl. XX.).

Fig. 35. — Cliff near Bacton.

6. Boulder-clay (lower division) with fragments of shells.

5. Sandy flint-shingle with seams of laminated clay (x) and fragments of wood ; shells at places in lower part of the shingle, 10 to 12 feet.

5'. Elephant-bed 1/2 to 1 foot.

4. Top of Forest-bed.

  • Mr. Crowfoot's Collection.