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V] of these I was able to gather a clear idea of the changes of sea-level which had aflected this part of South Wales. The following sequence was met with:—

Strong line of erosion.

4. Blue silt with many sedges, and at the bottom a few foraminifera.

5. The Upper Peat Bed, about four feet below Ordnance datum and fairly constant in level. It ranges from one to two feet in thickness, and where fully developed it presents the following details:—

5 a. Laminated peat with logs of willow, fir and oak, passing down into

5 b. Light-coloured flexible marl composed of ostracoda with much vegetable matter.

5 c. Shell-marl composed principally of Limnaea, Bythinia, etc., with ostracoda and much vegetable matter. This seam must have been formed in a nearly freshwater tidal marsh; it yielded Najas marina, a plant now confined to Norfolk.

5 d. Peat with logs of oak, etc. A Neolithic worked flint was found by Mr Storrie in this seam, three inches below the shell-marl. This implement