563 



granite of Devon. Lastly, they describe granite veins and elvan 

 dykes as traversing tiie Culm Measures, 



The conclusion is, that no rocks in Devon or Cornwall are older 

 than the Upper or Middle Cambrian ; that a magnificent develop- 

 ment of the Upper Cambrian terminates in the ascending order about 

 the base of the Silurian system ; that these rocks are surmounted by 

 an immense culmiferous trough, the upper portion of'which is identical 

 in fossils with the upper division of our coal measures; and that the 

 granite is posterior to a'.l these, but probably anterior to the new red 

 sandstone. 



A paper was then communicated, '' On the upper formationsof the 

 New Red System in Gloucestershire, Worcestershire and Warwick- 

 shire, showing that the Red (Saliferous) marls with an included band 

 of sandstone, represent the Keuper or Marnes irisees, and that the 

 underlying sandstone of Ombersley, Bromsgrove and Warwick, is 

 part of the ' Bunter Sandstein,' or * Gr^s bigarre' of foreign geo- 

 logists;'' by Roderick Impey Murchison, F.R.S., V.P.G.S., and 

 Hugh E. Strickland, Escj., F.G.S. 



In previous communications* Mr, Murchison has shown, that the 

 system of New Red Sandstone in the central counties of England 

 is divisible into four formations. 1. Marls with salt and gi/psum, and 

 one included band of sandstone, (Foreign Equiv. Keuper or marnes 

 irisees.) 2. Quartzose Sandstones, (Bunter Sandstein, or Gres bi- 

 garre.) 3. Calcareous Conglomerate, representing the magnesian 

 limestone or dolomitic conglomerate, (Zechstein, &c.) 4. Lower 

 New Red Sandstone, (Rothe todte liegende.) 



The object ofthe present communication istomark, with precision, 

 the distinctive characters ofthe two upper formations of this system, 

 and to point out how the one can be separated from the other over 

 a wide area, by stratigraphical, lithological, and zoological distinc- 

 tions. 



The rocks are described in descending order. 



1. Red and Green Marls and Sandstone, (Keuper.) — This for- 

 mation includes all the variegated marls which lie between the 

 lowest beds of Lias, and the uppermost strata of the underlying 

 formation of sandstone. 



The highest of these marls graduate into the lias, are occasion- 

 lly gypseous, and at a depth of about 200 feet beneath the lias, 

 are underlaid by a peculiar sandstone, which appears to have escaped 

 the notice of former observers. 



Tracing this rock from tlie borders of Gloucestershire, through 

 Worcestershire into Warwickshire, the authors show, by various 

 sections at Burg Hill, Ripple, Wallsfarra, Inkberrow, Hervington, 

 and Shrawley Common, that this band, which never exceeds forty 

 feet in thickness, invariably occupies the same stratigraphical 

 position. It is a thin bedded, hardish, quartzose sandstone, usually 

 of whitish colour, but sometimes tinted light green and red ; the 

 grains of sand being frequently cemented by decomposed felspar, 

 * Proceedings, vol. i, p. 471 ; vol. ii, p. 115. 



