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 GEOLOGY one of those vexed questions that is really of little consequence. There is not the least doubt that the Rhsetic Beds are passage-beds between the Trias and Lias, but they are generally grouped in this country, as abroad, with the Trias. Curiously enough there is evidence in the vicinity of Bridgend in South Wales of red marly beds on the horizon of the black Rhstic shales, showing that conditions similar to those which attended the deposition of the Keuper Marls locally occurred in Rhstic times. This fact has lately been brought into notice by Mr. R. H. Tiddeman. It is worthy of remark that while beds of White Lias occur near Shipston-on-Stour, as they do at Bath and towards the Mendips, they are nevertheless absent or poorly represented over great part of Gloucester- shire and South Worcestershire. A peculiar layer, called the ' Guinea Bed,' has been observed by Mr. Tomes in Warwickshire,^ and this contains an admixture of Lower Lias with Rhsetic fossils. It is not im- probable, therefore, that there was locally an irregular overlap of the Rhxtic Beds, accompanied by reconstruction of some layers, during the changing conditions which ushered in the Lower Lias.^ LIAS AND OOLITES Following the Rhstic Beds we have the three divisions of the Lias. A considerable portion of Worcestershire is occupied by the Lower Lias, which consists of a group of argillaceous limestones, overlain by a thick mass of blue and grey clays with only occasional bands of limestone. The basement limestones are exposed along the scarps from Strensham, Hill Croome, Croome d'Abitot, to Stoulton and Hanbury, east of Droitwich, and they extend near the surface over the northern portions of the Lias area in the county, and again at Hasler Hill, near Evesham, Cleeve Prior, and the neighbourhood. Numerous quarries have been opened in the beds, though fewer are now worked than was the case in past times. Outliers occur at Bushley and at Berrow to the south-east of the Malvern range. These lower beds of limestone, which are interbanded with shales, are not much more than 20 feet in thickness, and some of the layers are fissile and banded. They yield plant-remains, Crustacea, such as Eryon, also Ammonites johnstoni, and in the lowest layers Pleuromya crow- combeia, and many examples of Ostrea liassica. Remains of the large reptiles Ichthyosaurus and Plesiosaurus are also found, as well as the fishes Dapedius and Pholidophorus. The stone is burnt for lime, while some smooth and even-grained slabs are used for inside paving, others for steps, tombstones, etc. In several locaHties the surface beds of limestone have been disturbed, a feature to which further reference will be made. ' Quart. Journ. Geol. Soc, vol. xvi. p. 394 ; vol. xxxiv. p. 182. ^ ' Lias of England and Wales,' Mem. Geol. Survey, p. 151. 19