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 A HISTORY OF CORNWALL remains reposing on the sand, the relics of a wood mainly composed of hazel, and to a smaller extent of alder, elm and oak ; while hazel-nuts and the remains of insects, especially of beetles, are abundantly preserved. A small portion of a submarine forest occurs at Millendreth Bay near Looe. Another at Maen Forth to the south-west of Falmouth has been described by the Rev. Canon Rogers, who observed the stump of an oak in its position of growth with peaty material enclosing its roots and containing the remains of the common yellow flag (Iris pseudacorus] still flourishing in the adjoining swamp. 1 He also noticed the remains of a submarine forest with stumps of oaks and willows in their original situations a little above the level of low water at Porthleven near Helston. Mr. Nicholas Whitley has described another at Porthmellin. In the Hayle estuary, the Dunbar Sands at the mouth of the canal at Perran Forth, Lower St. Columb Forth, Mawgan Forth, and numerous other localities, traces of submarine forests also occur. In 1898 we observed a tree stump detached from its original position on Pendower beach in Gerrans Bay, indicating a submarine forest in that vicinity. The subsidence of the land which these forest beds imply is con- firmed by the evidence of the deposits which line the mouths of our estuaries. The search for stream-tin has been the means of dissecting these accumulations below the level of the sea, both at Restronguet Creek and at Pentuan, where remains of a forest growth in its natural position are buried beneath an accumulation of deposits exceeding 50 feet in thickness, which overlies the stream tin. At Pentuan, Mr. Colenso, in 1829, found roots of the oak in their natural position at the base of this deposit with oyster shells still fastened to some of the stumps. These were overlain by a stratum of dark silt, about a foot in thickness, on the top of which was spread a layer of like extent formed of the leaves of trees, hazel nuts, sticks and moss, the moss in a perfect state of preservation, and affording evidence of having grown in the position where it was found. This latter layer occurred at a depth of about 30 feet below the level of low water, and supported a stratum 10 feet thick sprinkled with wood, hazel nuts, together with the bones and horns of deer, oxen, etc. ; and shells of the same species as those which now exist in the neighbouring sea arranged in layers in such a position as to suggest that the animals lived and died where their remains were found. In an overlying bed of sand, 20 feet in thickness, were the remains of trees lying in all directions, together with the relics of red deer, and the bones of whales. This in its turn was overlain by another bed of sand and gravel 20 feet thick, which extended to the surface. On the upper portion of the superficial layer, on the level with the low water at spring tides, were found the remains of a row of wooden piles, apparently used in the con- struction of a footbridge, which, if correct, would imply a subsidence of the land since that portion of the human era when man had reached the stage capable of such construction. 1 In the submerged forest at Maen Forth Mr. Samuel Roberts discovered the horns of a deer at present in the possession of Mr. Robert Fox of Falmouth. 8