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ber of the coal series. This division is unimportant on the east of 

 Coalbrooke Dale, but in the western part of Salop it swells out and 

 corresponds with the dolomitic conglomerate of Bristol. At Car- 

 deston it is from eighty to one hundred feet in thickness j its es- 

 carpment, with partial interruptions, may be traced from Alberbury 

 and the Brythins round the carboniferous promontory of Salop 

 and the Clent Hills, and it forms a distinct ridge between Bridge- 

 north and Kidderminster. 



4. Beneath this, in Salop and Worcestershire, is found a thick 

 deposit of reddish sandstone (rothe todte liegende) ; it passes up- 

 wards into dolomitic conglomerate, and downwards into the coal- 

 measures in conformable beds, so that there is great reason to sup- 

 pose that unwrought coal lies beneath. Mr. Murchison has deter- 

 mined the extent of this rock, which occasionally towards the bot- 

 tom contains trappean conglomerates like those of Heavitree in 

 Devon, or feldspatic rocks like those of the Malvern and Abberley 

 range. 



The dolomitic conglomerate just mentioned has in another coun- 

 ty engaged the attention of the Rev. David Williams : he has dis- 

 covered for the first time Saurian reptiles in this deposit. Mr. Co- 

 nybeare had before noticed the occurrence of a part of the skeleton 

 of a supposed gavial near the bottom of the red sandstone in Wor- 

 cestershire. 



The obscurity which for so many years continued to involve the 

 red sandstone deposits both in England and on the Continent was 

 first cleared away by Professor Sedgwick. We now know that the 

 proper position of the rothe todte liegende of the Germans is im- 

 mediately beneath the magnesian limestone, and that it is the same 

 rock which Mr. Smith described as the Pontefract sandstone. It 

 is much to be regretted that Mr. Hoffmann in the beautiful map 

 and sections which he published of North-western Germany, has 

 designated by one name, as if they were only parts of one and the 

 same deposit, the red sandstones and conglomerate that lie under 

 the carboniferous series, and those that lie above it. This grouping 

 together of formations so widely separated in nature is very objection- 

 able. With a view to distinctness it is essential that the rothe todte 

 liegende shall not be classed as heretofore, sometimes with the old 

 red sandstone, sometimes with the new, sometimes with both, some- 

 times with the coal-measures, but that it should hold the rank of a 

 substantive and independent formation. The barbarous phrase, 

 which has just been employed to designate it, though tolerated in 

 Germany, will never, it is hoped, be naturalized here. The name 

 by which it is known at Tarnowitz is too local. Many other names 

 have been proposed when one would have sufficed. By M. de 

 Beaumont it is called Gres des Vosges; by Mr. Smith, the Ponte- 

 fract rock ; by Professor Sedgwick, the Plumpton ; and by Dr. 

 Hibbert, the Roslyn sandstone. Assuming that all these names are 

 synonymous, the last appears for many and obvious reasons the 

 most worthy of adoption. 



This important rock, which, in richness of soil, in undulation of 



