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Rh town water supply; it passed through 226 feet 6 inches of these beds, the upper of which were chiefly marls.

These so-called Lower Permian rocks have yielded very few fossils; fragments of the cryptogamic plants Lepidodendron and Catamites have been recorded from a quarry near Exhall, and silicified trees at Allesley and Meriden. Obscure casts of a shell supposed to be Stropbalosia occurred at the Exhall quarry, and remains of a labyrinthodont reptile, Dasyceps bucklandi (Huxley), were discovered in a quarry at Kenilworth. Some of these are preserved in the Warwick Museum.

There is some reason to think that Spirorbis limestone bands may occur in these rocks at Whitacre Hall (near Nether Whitacre), for Mr. Howell records that such limestone was formerly burnt there.

Of late years evidence has been accumulating tending to show that similar rocks in other districts are very closely related to the Coal Measures. In the Wyre Forest coalfield district in Shropshire, and also in the North Staffordshire coalfield, rocks in all respects similar to these of Warwickshire contain Spirorbis limestones and thin coals. Nor is there in Warwickshire any evidence of a lapse of time or of abrupt changes of any sort at the base of these rocks: the Spirorbis limestone band in the ordinary Coal Measures is everywhere present at about the same distance below these 'Permian' beds. The occurrence west of Polesworth of what seemed a small isolated tract or outlier of these rocks apparently situated on lower beds of the Coal Measure series gave colour to the supposition that here the 'Permian' rocks are unconformable to the beds below; but this has been lately disproved by Mr. Fox-Strangways, who finds that the supposed 'Permian' here is a band of red-coloured sandstone in the ordinary Coal Measures themselves.

It thus becomes evident that the so-called Permian rocks of Salopian type—named thus from their typical development in Shropshire are linked on to the Coal Measures both stratigraphically and palæontologically, and should therefore be included in the Carboniferous system.

TRIASSIC

The rocks we have been hitherto describing form an isolated area surrounded on all sides by a great spread of red sandstones and marls which constitute the Trias. The delta and lagoons and jungle swamps of the Coal Measures had passed away; the red 'Permian' beds had succeeded, deposited it would seem in a slowly sinking area of land-locked lakes or almost wholly enclosed lagoons, the waters of which were highly charged with iron salts and unfavourable to animal life. At the close of this 'Permian' period great movements took place which resulted in the raising up of large areas of land, which were forthwith subjected to erosion. There seems to have ensued a state of things in