Raised .Beaches.
The Shelly gravels and sands of some tracts near Ridgmont, in Holdernese, may possibly deserve this name, but it is more certainly applicable to some Shelly sand-beds on the cliffs near Filet', from which several marine shells of existing species have been extracted.
Diluvial Deposits.
Accumulations of local gravel are common in the valleys of most parts of Yorkshire, but over great breadths of the district of Holder nese, in some of the oolitio and chalk hills, and in many of the valleys in these formations—over great part of the area of the central Vale of York—in the elevated country between the Swale and the Tees, and in a very few situations in the valley of the Calder, occur abund ance of stones of various eizesessad qualities, which have been drifted from great distances, even from beyond the limits of the county, espe cially from the north or north-west. Of these stones some are of a size to arrest attention, and of such a peculiar nature as to bo easily referred to the original situation from which they were drifted. Such in particular are the 'erratic blocks ' of porphyritic granite, which lie near the surface in many situations in the northern and eastern parts of Yorkshire, on areas which converge to the north-west, and finally terminate in the porphyritic granite fells of Shap, in West morland. From that point they were certainly removed across ridges of hills, and great breadths and valleys, as far as Flamborough Head and Scarborough ; but whether by force of water when the land was at a lower level or was rising out of the sea, or by icebergs floating on water, or by glaciers moving across the laud, or by is combination of these, is perhaps still a problem for discussion. A cousiderablo pro
portion of small drifted stones lies is a great body of clay which is not stratified, and iucloses stones of all sizes, without any arrange ment of size, gravity, or mineral quality. Bones of the elephant, hippopotamus, horse, ox, &c., occur in these gravelly and argillaceous deposits, but not frequently, except in valleya where the materials may have been displaced and subjected to fluviatile action. (Vale of York ; Middleton, On the Welds, &c.) Ossiferous Deposits.—At Hessle Cliff, flinty gravel, stratified under diluvial clay, contains elephantoid and other remains ; at Beilbecks, near Market Wei.;hton, marls which have some drifted gravel below and other gravel above, contain bones of the elephant, rhinoceros, fella, urns, and many other animals, with 13 species of land and fresh water shells of existing species. Few of the numerous caverns in Yorkshire, which occur in the great limestone districts of the North Riding, have been explored for bones. The Cave of Kirkdale has been rendered famous by Dr. 13ucklaud'e descriptions (` Reliquire Dilu vianse'), which enumerates more than 20 vertebrated animals among the reliquire.
Tertiary.
On the seacoast, immediately north of Bridlington Quay, grceu and ferruginous sands cuter into the composition of the cliff, and, under favourable conditions of the tide, have been explored with success, and have yielded a considerable number of ahells of tertiary date, perhaps of the age of the crag of Suffolk, in which some of the species certainly occur.