NEW RED SANDSTONE. 20/ 



NEW RED SANDSTONE OR POIKILITIC. 



The term New Red Sandstone was originally applied to 

 the red rocks that occur between the Coal-measures and the 

 Lias, and it was used by Conybeare to distinguish these strata 

 from the Old Red Sandstone, which underlies the Carboni- 

 ferous rocks. Subsequently the New Red Sandstone was 

 divided as follows : — 



Trias. 

 Permian. 



The name * Poikilitic ' (or Poecilitic, from poikilos, meaning 

 variegated) was likewise suggested by Conybeare as an 

 equivalent term for New Red Sandstone. In their general 

 lithological characters there is a marked similarity through- 

 out the Permian and Triassic series, consisting as the rocks do 

 of red, yellow, and variegated sandstones, conglomerates, and 

 marls, with occasional beds of limestone. 



The group forms a conspicuous band, stretching across 

 England from the mouth of the Tees near Redcar and 

 Hartlepool, to the mouth of the Exe, with a branch 

 running to the mouth of the Mersey ; thus marking off 

 the Palaeozoic ground of the North of England, of Wales, 

 and of the S.W. of England, from the Secondary and Tertiary 

 tracts, which lie to the east and south-east. Another tract of 

 the Red rocks occupies the Vale of Eden to the north and 

 east of the Lake District. 



The Permian and Triassic rocks, from their prevailing red 

 colour, are equally prominent in the landscape, and the ' red 

 ground ' and ' red rocks ' have given names to hamlets, 

 villages, and towns, such as Retford, Radford, Radcliffe, 

 Radstock, etc. : there is also the village of Redmarley 

 Dabitot, in Worcestershire, between Newent and Upton-on- 

 Severn. The red cliffs between Seaton and Torquay are 

 striking features in our coast scenery ; while the red soils, 

 and the deep red lanes mark the country in many places 

 inland. 



As before mentioned, the Permian and Triassic beds have been 

 differently classed by geologists. On physical grounds Sedgwick 

 grouped the Permian rocks with the Trias, while John Phillips 

 first suggested that the Magnesian Limestone should on palseonto- 

 logical grounds be classed as Palaeozoic ; but he subsequently 

 united the Permian and Triassic rocks under the general heading 



