^Ol. 57.] PBNDLESIDE GROUP AT PENDLB HILL, ETC. 387 



The late James Spencer gave the following list of plant-remains 

 from Horse Bridge Clough : — 



Lepidodendron. 



Sigillaria. 



Stigmaria. 



Calamites. 1 And ferns in abiind- 



Dadoxylon. ance. 



Artesia. 



Messrs. J. Barnes & W. F. Holroyd also note from the same 

 horizon at Marsden : — 



Neuropteins sp. 

 Sphenopteris sp. 



Lepidodendron. 

 Calamites. 



Sigillaria. 

 Lepidostrobus. 



Elsewhere, except at Congleton Edge Quarry below the marine 

 bed, we have not been able to obtain plants sufficiently well 

 preserved to be definitely named. 



The following table (p. 388) of life-zones which is here suggested 

 for the British Carboniferous rocks is constructed on broad lines, and 

 some of the larger zones contain sub-zones which are merely indicated 

 by the names of the zone-fossils. It will be seen that we are unable 

 to establish sub-zones at present for the great zone of Productus 

 giganteus. An examination of the table of fossils in Appendix A 

 (facing p. 402) shows that at present no species has been found to be 

 confined to any definite part of the Carboniferous Limestone Series. 

 This was the conclusion arrived at by the late George Morton, who 

 spent many years of careful work in the examination of, and col- 

 lecting from, the various beds of the Carboniferous Limestone Series 

 of North Wales. 



The subdivision of the Carboniferous Series on palaeontological 

 grounds is not in accord with the generally accepted classification 

 of the British Carboniferous rocks into Coal-Measures, Millstone Grits, 

 Yoredale Shales, and Carboniferous Limestone Series. It is dis- 

 tinctly shown that the main palaeontological divisions are 

 twofold, with a secondary subdivision of each main 

 group. With regard to the upper group, the separation of the Lower 

 Coal-Measures from the Millstone Grits is not borne out, nor can the 

 Pendleside Limestone Group be separated from the Millstone Grits ; 

 but the whole sequence is one well-marked series characterized by 

 a very definite fauna, and the palaeontological break only comes in 

 at the base of the Middle Coal-Measures. Beds of coal are found 

 at several horizons in the Millstone Grit Series, and even in some few 

 localities in the Pendleside Group (Congleton Edge), though not of 

 any economic value. 



When the extremely local character of the Millstone Grits and 

 the Pendleside Group is once recognized, it will be evident that the 

 stratigraphical lines of the older classification cannot be carried over 

 any extent of country, and hence the peculiar mistake which placed 

 the Yoredale Series of Wensleydale as the equivalents of the 

 Pendleside Group. AVould any geologist who was surveying Wales, 

 Ireland, Scotland, or England north of the Tyne only, ever have 



