28 ON THE UPPER CARBONIFEROUS STRATA OF SHROPSHIRE ETC. 



found in Triassic strata near Runcorn, and several Calamites in the 

 water-stones of Lymm, near Warrington. Gradually, therefore, I 

 doubt not, the land-surfaces of the period of the dark red sandstone, 

 as well as of the overlying Triassic beds, will be discovered, and the 

 connexion be traced between the plants of the great Carboniferous 

 era and those of succeeding ages. 



EXPLANATION OF PLATE I. 



A. Diagram sections showing the correlation of Upper Carboniferous or Per- 



mian strata. Scale 1 in. to 200 yards. 



B. Section of strata from Chirk, Denbighshire, to Ifton Heath, Shropshire. 



Scale 1 in. to 250 yards. 



