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 A HISTORY OF STAFFORDSHIRE may be said regarding the prevalent opinions as to its mode of formation. The one most in vogue regards each seam as representing an ancient bed of vegetation, and the usually accompanying underclay or fireclay as the soil on which it grew. Another opinion considers that some at least of the coals are made up of floated vegetable matter, tranquilly deposited in still water at a time when other sedimentation was at a standstill. Under either view there cannot be any doubt that each seam indicates a pause of more or less duration and of frequent recurrence throughout the Coal-measure period. 1 PERMIAN SYSTEM The red sandstones and marls succeeding the Halesowen Sandstone group have been regarded as belonging to a special type of ' Permian ' developed only on the west side of the Pennine Chain, but recent borings in Nottinghamshire have clearly shown the same type to be present on the east side of the Pennines. The limitation of the Permian system therefore needs revision, but it would be superfluous to discuss this ques- tion here. The red strata overlying the grey Halesowen Sandstone group are succeeded conformably by another set of red sandstones and marls with lenticular bands of calcareous conglomerates, which in turn are overlain by the so-called ' Trappoid Breccia ' of the Clent Hills (on the northern boundary of Worcestershire). These rocks have been classed as Middle Permian. 2 Very much the same succession occurs round Enville, but above the ' Trappoid Breccia ' a set of red marls with an intercalated band of breccia conformably follows, and has been regarded as forming an Upper Permian sub-division. Whether these distinct groups of rocks are the equivalent of the continental Permian system or not, it is beyond dispute that in this country they are intimately related to the Coal-measures, but separated from the Triassic system by one of the greatest unconformities known in British geology. On the other hand the Magnesian Limestone Series of the eastern counties considered to be the equivalent of the Permian Zechstein of Germany is removed from the highest Coal-measures by a strong unconformity, but is hardly separable from the Triassic deposits. The breccia bands which characterize the South Staffordshire ' Permian Rocks ' retain a general lithological facies throughout the district. Set in a sandy or marly paste, angular fragments or blocks of volcanic rocks, mingled with others of fossiliferous, Carboniferous, Silurian and Cambrian sandstones and limestones, show the varied source of their derivation. Their origin has therefore led to much con- 1 For a recent discussion on this interesting subject see Report of the British Association (1901), Bradford. at Franldey Lodge farm in the Clent area by T. C. Cantrill (Summary of Progress of the Geological Survey for 1901), pp. 63, 64. 18
 * Quite recently a band of Spirorbis limestone has been discovered in the so-called Middle Permian