Page:Transactions of the Geological Society, 1st series, vol. 4.djvu/215

 green colour is contrasted with the dark foliage of the elm, which is the prevailing tree of the county, very few oaks of considerable size being now found.

The limestone district has as yet produced little but heath and fern, the rock in general approaching too near the surface to be favourable to vegetation. Much of it however has been lately enclosed on the southern side of the river, and a part of that is of good promise. Within the limits of the sandstone and of the breccia there is very fertile grazing land.

Note on Magnesian Breccia.

By HENRY WARBURTON, Esq.

[Read 21st June, 1816.]

great stratum of magnesian limestone which passes from Sunderland in the north of England through the centre of the midland counties, suddenly terminates, as is well known, in the vicinity of Nottingham; and I am not aware of its reappearance in the south of England having been noticed except perhaps on the north-eastern border of the Ashby de la Zouch coal-field, where it is said to occur in great insulated masses.

The geological relations of this rock to other strata. appear to have been well ascertained in the northern and midland counties, where it is described as forming horizontal beds, and as lying under and parallel to the red marl, or occasionally as alternating with it. It has been ascertained by numerous sinkings in the same counties that the