remains. Buccinum, Trophon, Littorina, Cardium, and Ostrea are abundant in the gravel at March.[1] In the valley of the Nene, near Peterborough, oysters and other marine shells occur, mixed with those of land and freshwater origin. In Whittlesea Mere, remains of walrus and seal, and sea shells are found; while so far south as Waterbeach, less than ten miles from Cambridge, remains of whale have been discovered.
The old land-surface having been thus destroyed, we cannot with certainty trace the course of the ancient representative of the river Lark, below Mildenhall; it seems, however, to have proceeded northwards by Eriswell and Lakenheath, to join the Little Ouse. At Eriswell, a gravel of the same character as that near Mildenhall, occurs on the slope of the hill towards the Fen; but in it, as yet, few implements are recorded to have been found. At Lakenheath, however, they occur in the gravel now capping the hill overlooking the Fen, as well as on the slope.
Owing to the distance of these beds from any existing rivers, the late Mr. Flower[2] found great difficulty in reconciling them with any theory which would account for their presence by the action of rivers. If, however, we regard the great denudation of the Fen, country as subsequent in date to the deposit of the gravels, it appears to me that any difficulty on this point vanishes. That this denudation was in fact, at all events in part, subsequent to the deposit of the gravels, is proved by the position of the beds at Shrub Hill, which there cap a small area of Gault, and which, being above the general level of the Fens, can hardly have been deposited in the position they now occupy, when the configuration of the country was at all like what it now is. Such beds must, on the contrary, have been deposited in the bottom of a valley; and it appears as if in this case, by their superior hardness to the clay around them, or from some other accidental cause, they had protected this small spot from tidal action, which in the adjacent river, previously to the construction of Denver Sluice, extended nearly as far as Brandon.
The rolled condition of so many of the implements found at Shrub Hill, proves that they must have been transported some distance by water, from beds of a higher level.
Turning now to the existing valley of the Little Ouse, we find, at Brandon Down, the gravel occupying the summit of a high ridge of land almost at right angles to the present course of the
- ↑ H. G. Seeley, Q.J.G.S., vol. xxii. p. 472.
- ↑ Q.J.G.S., vol. xxv. p. 455.
