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Show 174 OLDER PLIOCENE PERIOD. L Ch. XIII. direction of the strata, and the crag affords most interesting illustrations of this phenomenon. In the sea-cliff near Walton, in Suffolk, opposite the Martello Tower, called R, the section represented in the annexed diagram is seen. The vertical height is about 20 feet, and No. 31. Section of sl1elly crag 11ear Walton, Suffolk. the beds consist alternately of sets of inclined and horizontal layers of sand and comminuted shells. The sand is siliceous and of a ferruginous colour, but the layers are sometimes made up of small plates of bivalve shells, arranged with their flat sides parallel to the plane of each layer, like mica in micaceous sandstones. The number of laminre in the thickness of an inch, both in the siliceous and shelly sand, varies from seven to ten in number, so that it is impossible to express them aU in the diagram. The height of the uppermost stratum is, in this instance, remarkable, as it extends to twelve feet. The inclination of the laminre is about 30° ; but in the cliffs of Bawdesey, to the eastward, they are sometimes inclined at an angle of 45o, and even more. No.32. Section at tile lightl!uuse near Happisborougl1. Height sixteen feet. a, Pebbles of chalk flint, and of rolled pieces of white chalk. b, Loam overlying a, c, c, Blue and brown clay. Ch. XIII.] CRAG OF ENGLAND. 175 This diagonal arrangement of the layers, sometimes called 'false stratification,' is not confined to deposits of fine sand and comminuted shells, for we find beds of shingle disposed in the same manner as is seen in the annexed section (No. 32). The direction of the dip of the inclined layers, throughout the Suffolk coast, is so uniformly to the south, that I only saw two or three instances of a contrary nature, where the inclination was northerly. One of the best examples of this variation is exhibited in a cliff between Mismer and Dunwich, wood-cut No. 33. In this case, there are about six layers in the thickness of an inch, and the part of the cliff represented is about six feet high. No.33. Stction of pm·t of Little Cat cliff, composed of quartzose sana, sllowing tl1e incli11ation of the layers in opposite directions. Another example may be seen near Walton, where the layers, which are of extreme tenuity, consist of ferruginous sand, brown loam, and comminuted shells. It is not uncommon to find in this manner sets of perfectly horizontal strata 1·esting upon and covered by groups of wavy and transverse layers. No.34. Lamination of sllelly sand ana loam, near tlle Signal-lwuse, Walton. Vertical height jour feet. The appearances exhibited in the diagrams are not peculi-ar to the crag, and I have seen sand and pebble-beds of all ages including the old red sandstone, greywacke, and clay-slate: exhibit the same arrangement, |