38 EXPLANATION OF PLATE 26'". 



which lies in the middle region of that large, and widely 

 extended series of Sandstones, and Conglomerates, Lime- 

 stones, and Marl, which English Geologists have usually 

 designated by the common appellation of the New red 

 Sandstone Group, including all the strata that are interposed 

 between the Coal formation, and the Lias. 



M. Brongniart, in his Terrain de VEcorce du Globe, 1829, 

 has applied to this middle division the very appropriate 

 name of Terrain Poscilien, (from the Greek voixiXog), a term 

 equivalent to the names Bunter Sandstein, and Gres bigarre, 

 which it bears in Germany and France ; and indicating the 

 same strata which, in England, we call the new Red Sand- 

 stone. (See Plate 1. Section No. 17.) 



Mr. Conybeare, in his Report on Geology to the British 

 Association at Oxford, 1832 (Page 379, and P. 405, Note,) 

 has proposed to extend the term Poecilitic to the entire 

 Group of strata between the Coal formation and the Lias; 

 including the five formations designated in our section 

 (PI. 1, No. 15, 16, 17, 18, 19,) by the names of New Red 

 Conglomerate, Magnesian Limestone, Variegated Sand- 

 stone, Shell Limestone, and Variegated Marl. Some com- 

 mon appellative for all these formations has been long a 

 desideratum in Geology ; but the word Poecilitic is in 

 sound so like to Pisolite, that it may be better to adhere 

 more literally to the Greek root tfoixfXos, and apply the 

 common name of Poikilitic group to the strata in ques. 

 tion.* 



* The general reception of such a common name for all these 

 strata, and the reception of the Grauwacke series into the Cambrian 

 and Salurian systems, as proposed by Professor Sedgwick and Mr. 

 Murchison, will afford three nearly equal and most convenient groups 

 or systems, into which the strata composing the Transition and Se- 

 condary series may respectively be divided ; the former comprehending 

 the Cambrian, Salurian, and Carboniferous systems, and the"latter com- 

 prehending the Poikilitic, Oolitic, and Cretaceous Groups. 



