The section of the Bedford tool-bearing alluvium, given in Figure 23, may serve to illustrate that of Icklingham, if we substitute Chalk for Oolite, and the river Lark for the Ouse. In both cases, the present bed of the river is about 30 feet below the level of the old gravel, and the Chalk hill, which bounds the valley of the Lark on the right side, is capped like the Oolite of Biddenham by boulder clay, which rises to the height of 100 feet above the Lark. About twelve years ago, a large erratic block, above 4 feet in diameter, was dug out of the boulder clay at Icklingham, which I found to consist of a hard siliceous schist, which must have come from a remote region. The tool-bearing gravel here, as in the case to which it has been compared near Bedford, is proved to be newer than the glacial drift, by containing pebbles of basalt and other rocks derived from that formation. CHAPTER 10. -- CAVERN DEPOSITS, AND PLACES OF SEPULTURE OF THE PLEISTOCENE PERIOD. Flint Implements in Cave containing Hyaena and other extinct Mammalia in Somersetshire. Caves of the Gower Peninsula in South Wales. Rhinoceros hemitoechus. Ossiferous Caves near Palermo. Sicily once part of Africa. Rise of Bed of the Mediterranean to the Height of three hundred Feet in the Human Period in Sardinia. Burial-place of Pleistocene Date of Aurignac in the South of France. Rhinoceros tichorhinus eaten by Man. M. Lartet on extinct Mammalia and Works of Art found in the Aurignac Cave. Relative Antiquity of the same considered. WORKS OF ART ASSOCIATED WITH EXTINCT MAMMALIA IN A CAVERN IN SOMERSETSHIRE.