ing upon the restricted area of the district under review. In order to explain the lowering of the bed of the Avon by an increased velocity of its stream, Strickland supposes a "farther elevation of the land," to quote his words; but it appears to me necessary to call in the agency of unequal elevation, the inland district of Warwickshire having risen more rapidly than the portion nearer the sea, as Sir C. Lyell supposes to have been the case in reference to the denudation of the Loess of the Rhine, if we are to resort to a cause of which, as far as I am aware, no collateral evidence exists.
Concluding Remarks.—It would be interesting to know how far the evidence afforded by the marine mollusca found in the drift of the Severn valley may be able to explain the probable conditions under which the latter was deposited. The late Edward Forbes, in his valuable paper "On the Geological Relations of the existing Fauna and Flora of the British Isles" remarks that, Littorinæ, Purpuræ, &c. are genera and species definitely indicating, not merely a shallow water, but a coast-line. Regarding the evidence at present obtainable from the mammalian remains found in the beds containing marine shells at Beckford, and in the neighbourhood of Worcester, and those from the freshwater gravels of the Avon and some of its tributaries, it appears that the number of species is much less in the former than in the latter.
In thus venturing to bring the subject of this paper before the notice of the Society, I may perhaps be allowed to state that I have no pet theory to support, and no inclination to throw "small stones" at those of others, my chief object being to leave the subject in such a condition that future observers may be able to take up its further investigation at the point where I have left off.
In conclusion, let me tender my best thanks to many kind friends for their zeal in forwarding the objects of the present inquiry.
Discussion.
Mr. Searles V. Wood, Jun., had long been aware of the existence of both the Chalky Boulder-Clay and the Middle Glacial Sand near Rugby. He pointed out the difference between the fauna of the sands of the Severn valley and that of the Middle Glacial sand of East Anglia, and thought it scarcely possible that the two sands could be identical.
Mr. Gwyn Jeffreys was doubtful as to the authenticity of some of the shells which had been brought to Mr. Maw. The fossil shells from the Severn valley, Wolverhampton, Manchester, and Moel Tryfaen were nearly identical, and indicated raised beaches. He thought it possible that a definite line of such beaches might eventually berecognized through that part of England.
Mr. W. Boyd Dawkins did not consider that Mr. Lloyd had shown any marked difference in the mammalian fauna of the Avon and Severn valleys. He had failed to discover any traces of Elephas ntiquus in either.
Mr. Prestwich thought that Mr. Lloyd had probably divided the
