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it a more rounded contour, and by its finely laminated character and bright red colour, as contrasted with the purplish and dull red of the highest beds of the Lower Keuper.

We come now to the most interesting feature of all that may he said to be new in the geology of this part of Nottingham. Running along the boundary line separating the Lower Keuper from the Bunter (f2) on the new map you will observe a narrow band coloured blue. That is the conglomerate forming the lowest bed of the Keuper in this district. It was seen at short intervals along the boundary all round the double tongue of Banter in the St. Ann's Valley; and, although tolerably persistent, it is sometimes represented by a mere string of pebbles. The tracing of this conglomerate along the base of the Hunger Hills and round the opposite side of the valley to where it was cut off by No. 2 fault in Dame Agnes Street fairly did away with the theory of the curved fault; for, according to the Survey map, this valley ought to have been in Lower Keuper. The best exposures of this conglomerate were in Turner Street and on Hunger Hill Road, the section in Turner Street having the advantage of showing a perpendicular section, while on the Hanger Hill Road it had to be studied during the process of excavating. In Turner Street its greatest thickness was 22in., and it there consisted of rounded and partially rounded pebbles of all sizes up to boulders five or six inches long, consisting for the most part of quartz and quartzite, with a few bits of brown magnesian limestone, volcanic ash, basalt, greenstone, chert, slaty rock, and Coal Measure rock, the whole being firmly compacted together by lime and magnesia and oxide of iron, the latter giving it a strongly ferruginous aspect. Such is its compactness, indeed, that navvies who happen to have to excavate it have learnt to dread it, and affirm it to be the toughest rock they ever met with. It rested in the shallow cavities of an eroded surface of the Bunter, sloping to the east at an angle of about 5°, and was surmounted by first about 18in. of coarse mottled sandstone, then beds of finely-laminated brown and light olive-green sandstone, with thin partings of red marl. At its outcrop on the top of the low rounded hill of Bunter on Hunger Hill Road, the conglomerate, which, with its associated beds, formed a band at the surface about 50ft. broad, had much the same composition as in Turner Street, only there was more chert and a good deal of white limestone in lumps and ground-up, there being also calcite in minute crystals, and as a thick coating to some of the pebbles; it was about eight inches thick, and covered by first a thin bed of greenish grit, cemented into cakes by calcareous matter, then by an irregular series of bods about three feet thick, consisting chiefly of unconsolidated white (bleached) sand, false-bedded, and streaked with pate green and yellow, with occasional strings of pebbles enclosing lenticular beds of sand, of a ferruginous colour. The whole, though very irregularly bedded, had a general inclination to the north-east, passing under the Keuper. When a perpendicular section of these beds was exposed further wider the Keuper, they presented a peculiar variegated wavy appearance, being streaked with red, yellow, and pale green. I was struck by the remarkable resemblance between these beds and the raised beaches I had seen on the sea shore, the only difference that I could perceive being the complete absence of any traces of life. Among the pebbles forming the conglomerate at this spot, I found what appears to have once formed the extremity of a sea-worn pinnacle of greenish fine-grained (Silurian?) sandstone, such as may be seen at the present day along coasts where Silurian or Cambrian rocks are exposed. That this was its origin seems to me to be indicated by its peculiar water-born aspect, and by the lateral grooves along the lines of stratification.

A very instructive section has lately been exposed in Ford Street,