NEW RED SANDSTONE. 209 



the representative of the Bunter division commences or terminates 

 in the series. 



The presence in Central Europe of the Muschelkalk, comprising 

 compact red and grey limestones with dolomite, about looo feet in 

 thickness, and the absence of this calcareous division from Britain, 

 has led to our series being regarded as incomplete ; but there is no 

 reason for doubting that other kinds of sediment may in this country 

 represent it.^ 



Near Nottingham there is evidence of the overlap of Permian 

 rocks by the Trias, which crosses some of its upper divisions, and 

 finally rests on the Coal-measures.^ Even here there is no positive 

 evidence of denudation between the Permian and Bunter forma- 

 tions, inasmuch as the overlap by the Bunter Sandstone may have 

 coincided with a depression of the area that took place after the 

 Upper Permian Beds were deposited. Similar instances of over- 

 lap are met with in other parts of the North of England ; and, as 

 Mr. E. Wilson has pointed out, the fluctuations in character and 

 thickness of the New Red rocks depend on the physical inequalities 

 and limitations of the areas of deposition, and on the contem- 

 poraneous inequalities of subsidence. Evidences of local and 

 contemporaneous erosion occur at all horizons in the New Red 

 series. 



From the occurrence of brine-springs and beds of rock-salt 

 in the higher portions of the New Red rocks, the term 

 Saliferous System has been employed for the entire series of 

 these rocks. 



In treating of the physical history of the Permian and 

 Triassic rocks of Great Britain, Sir Andrew Ramsay has 

 pointed out that the beds were deposited in great inland 

 lakes for the most part salt. One objection might be taken 

 to this theory, inasmuch as the organic remains of the 

 Magnesian Limestone are truly marine types. But these 

 are very much restricted when compared with those of 

 Carboniferous times, and in the poverty and dwarfing of the 

 forms, the fossils of this rock may be compared with the still 

 less numerous fauna of the Caspian ; so that they might have 

 lived similarly in a large inland salt lake which had previously 

 been connected with the open ocean.^ There were perhaps 



^ G. Mag. 1874, p. 385. On the subject of Permian and Trias, see Murchison, 

 Siluria, edit. 5, p. 327 ; W. T. Aveline, Geol. Nottinghamshire, etc., edit. 2 

 (Geol. Survey Map, 82 N.E.), p. 26; Rev. A. Irving, P. Geol. Assoc, iv. 52, 79; 

 G. Mag. 1874, p. 315; 1882, pp. 158, 272, 316; and 1884, p. 324; E. Hull, 

 G. Mag. 1882, p. 491 ; Q. J. xiv. 224; W. T. Aveline, G. Mag. 1877, p. 155 ; E. 

 "Wilson, G. Mag. 1880, p. 93. 



2 G. Mag. 1877, pp. 155, 239, 309. 



•* Q. J. xxvii. 189, 241. See also Prof. A. H. Green, G. Mag. 1872, p. 99 ; J. 

 G. Goodchild, Trans. Cumberland Assoc. No. ix. 1885 ; and E. Wilson, 

 Midland Naturalist, iv. 202. 



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