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44 another 10 fathoms, or 120 feet altogether. Unfortunately we cannot say from what deposit the large bones of extinct animals were washed; they may come from the sands below the moorlog, but it is quite as probable that the Pleistocene deposits formed islands in the ancient fen—as they do now in East Anglia, Holderness, and Holland.

More than one submerged forest may be present on the Dogger Bank. The masses of moorlog are usually dredged on the slopes at a depth of 22 or 23 fathoms; but at the south-west end it occurs on the top as well as on the slope, the sea-bottom on which the moorlog is found consisting of fine grey sand, probably an estuarine silt connected with the submerged forest, for the North Sea sand is commonly coarse and gritty.

With regard to the moorlog itself and its contents, it is possible that some of the mammals in the list, such as the reindeer, beaver, and walrus, may belong to this upper deposit; but we have no means of distinguishing them, as the bones were all found loose and free from the matrix. The insects and plants were all obtained from slabs of this peat.

The dredged cakes of peat handed to us for examination came from different parts of the Bank; but they were all very similar in character, and showed only the slight differences found in different parts of the same fen. The bed is essentially a fen-deposit of purely organic origin, with little trace of inorganic