Page:Quarterly Journal of the Geological Society of London, vol. 27.djvu/617

 of sand, and iron-sand, with fragments of wood, and flint-pebbles, together with clay-pebbles of the destroyed bed, which latter are in places so numerous as almost to hide its reconstructed character.

Immediately over this clay-bed is another series of sands and shingle " 5," which are often fossiliferous ; and when the clay- bed is wanting, it is difficult to draw a line of demarcation between the two series, especially as the fossils themselves, with the exception chiefly that the Tellina balthica is far more abundant, do not show any very marked difference. The shells I have found are : —

Cardium edule. Mytilus edulis.

Cyprina islandica.

Leda lanceolata. Purpura lapillus.

Mya arenaria. Littorina littorea.

Tellina balthica. — rudis.

— obliqua.

These, however, are, I believe, far from representing the fauna of this bed, which is undergoing, I understand, in the hands of the Messrs. Searles Wood, a thorough examination. The importance to be attached to these beds does not arise so much from their exhibition here, as from the circumstance that they will serve to determine the position and age of beds of sand and gravel, generally without fossils, which have a wide range in the south-east of England, and the exact position of which it is important to know in consequence of their bearing on many interesting problems connected with the denudation of the country. These beds, which overlie the Chillesford Clay and the Forest-bed, and are succeeded by the lower division of the Boulder-clay, I propose to designate the " Westleton Sands and Shingle."

As, however, some uncertainty may be considered to attach to the clay which we have referred in Norfolk to the Chillesford beds, on account of the absence of fossils and the presence also of laminated clays in the overlying beds, we prefer to commence our observations in a district where both the Chillesford Clay and the Crag- sands are distinctly developed, and where the relation of the several groups to one another is more clearly determined.

The Westleton Sands and Shingle.

Between Yoxford and Dunwich there rises, just above the village of Westleton, a ridge of low hills largely excavated at that spot for sand and gravel. Nowhere, except on the north-west of Henham Park, are these shingle-beds so largely developed. They attain a thickness of from 30 to 40 feet, and consist of a series of stratified beds of well-rounded flint-pebbles imbedded in white sand, and with two or three subordinate beds of light- coloured clay. They look more like the pebble-beds of Blackheath than any other beds in the eastern counties. Mixed with the flint-pebbles are a few small pebbles of old rocks, with a considerable number of white quartz- pebbles, the presence of which constitutes a distinctive feature of these beds throughout their range. No fossils are found here, and no other beds are exposed. Elsewhere this series is generally not