208 NEW RED SANDSTONE. 



Poikilitic.^ Thus, whilst the organic remains of the Permian rocks 

 are considered to bind them more closely to the Palaeozoic rocks 

 than to the Trias, in their lithological characters and in the 

 evidences of their method of formation, the two series are 

 inseparably connected, and with them the Rhaetic Beds may 

 conveniently be classed. Of course different groupings of strata 

 might be made on palaeontological grounds, by considering the 

 evidence of the land fauna and flora instead of the marine 

 organisms i'^ but in this country, as a rule, organic remains are 

 scarce, except in the Magnesian Limestone, which belongs to the 

 Permian series, and in the Rhcetic Beds, which occur at the top 

 of the Trias. 



The evidence of the Permian flora is not satisfactory, from the 

 fact that much of the " Lower Red Sandstone," originally grouped 

 as Permian, has proved to be iron-stained Coal-measures;^ hence 

 some of the plants recorded as Permian have in reality come from 

 older rocks. (See p. 170.) The unconformity between the Red 

 rocks and the Paleozoic rocks is generally very marked. This 

 is the case throughout the south-west of England ; and in Lancashire 

 and Yorkshire the unconformity is eqvially striking, for the Car- 

 boniferous rocks had evidently undergone great disturbance and a 

 large amount of denudation before the Permian epoch, so that the 

 newer strata rest indifferently on various members of the older 

 system.* (See Fig. 27, p. 183.) The symptoms of conformity 

 between Permian and Coal-measures, noted in a few localities in 

 the North of England, may in some cases be due to accidental 

 concordance in the lie of the strata, and in other cases to the 

 confusion which has arisen between the stained Coal-measures and 

 the Permian rocks. Thus Mr. D. C. Davies was of opinion that 

 at Ifton, in Shropshire, there is a passage upwards from the Coal- 

 measures into Permian rocks, and that the latter contain seams 

 of coal.^ This view, however, has not been supported. 



Some difficulties respecting our New Red rocks have arisen from 

 attempts to correlate their divisions with those recognized on the 

 Continent ; but in a great mass of false-bedded sediments, it is 

 not to be expected that beds of particular lithological character 

 will be maintained for great distances. Moreover, even in this 

 country it is not always easy to distinguish Permian from Triassic 

 rocks ; and in the case of the Bunter ' pebble-beds,' we have some- 

 times to apply the term to rocks that have few, if any, pebbles in 

 them. In Devonshire, where there is exposed a clear succession 

 of red rocks, it is questionable whether Permian is represented 

 as well as Trias, and it is not possible to say for certain where 



^ Geol. Oxford, etc., p. 94. 



- See Huxley, Address to Geol. Soc. 1870 ; P. M. Duncan, Address, 1S77 ; 

 also W. T. Blanford, Q. J. May, 1SS6. 



2 R. Howse, Ann. Nat. Hist. (2), xix.'37; see also J. W. Kirkby, Nat. Hist. 

 Trans. Northumberland, iii. 



* E. W. Binney, G. Mag. 1866, p. 49. 



^ Q. J. xxxiii. 10 ; and xli. 107 (Proc). 



