46 ON THE PERMIAN BEDS OF SOUTH LANCASHIRE. 



they are really unconformable to each other. The marls 

 in the same locality appear to pass into the conglomerate, 

 and the latter into the soft red sandstone of Collyhurst. 

 These three divisions of the permian beds, although not 

 always conformable to one another, are clear and distinct, 

 and would hold good not only through Lancashire, but in 

 Westmoreland and Cumberland. The marls are the only 

 strata containing permian fossils, as the two latter strata up 

 to this time have yielded none. Now, if the term permian 

 were applied to these, no difficulty would arise ; but when 

 the coarse pebbly sandstones of Astley, lying under the 

 last-named strata, and containing common coal-plants of the 

 genera Sigillariaj LepidodendroTij Calamites, &c., beds very 

 similar to thoseoftheBallast Quarry near Moirain the Ashby- 

 de-la-Zouch coal-field, are included, we are obliged to di- 

 stinguish them j accordingly, in my second paper, printed in 

 the Society^s Memoirs, they have been called lower permian. 

 They occur just under the red marls containing lime- 

 stones and fossils of the genera Schizodus, Bakevellia, &c., 

 and where the conglomerate and soft red sandstone ought 

 to have been, if those strata had been conformable to 

 the overlying red marls. The lower permian are not 

 only unconformable to the overlying upper permian, but 

 also to the underlying upper or Manchester coal-field. 

 The chief circumstance which induced me to remove them 

 from the carboniferous strata was the conglomerate cha- 

 racter of some of the sandstones, which are as full of 

 white-quartz pebbles as millstone grits are. Now, in the 

 Lancashire coal-field a considerable part of the lower, and 

 the whole of the middle and upper coal-fields, comprising 

 strata to the extent of 5000 feet, have never in Lancashire, 

 so far as my knowledge extends, afibrded a quartz pebble of 

 the size of a pea; so the change of physical characters 

 caused me to class the Astley beds under lower permian, 

 rather than upper coal-measures. They undoubtedly occupy 



