TRANSACTIONS OF THE SECTIONS. 69 



1, C'ervtis megaceroa occurs in the grey clays underlying the peat, 'which, in 

 1 inland districts of Lancashire, is replaced by marine sands and shingle 



England, 

 the main 



■with recent shells resting on the Boulder-clay. A submerged forest invariably 

 occurs on the base of the peat, and is well seen on the coast or the mouth of the 

 River Alt, near Liverpool, on the coast of Wirval, in Cheshire, and at Rossall, near 

 Fleetwood : at the latter place a horizon of Scotch Fir is found beneath one of Oak ; 

 occasionally Beech most occurs both at the base and at higher horizons in the peat, 

 overlying which at Rossall occurs Tidal Alluvium, in which were discovered a large 

 number of Roman coins, which gives a pre-Roman date to the growth of the thick 



Seat of Lancashire. In Cheshire there is a very similar sequence, and Neolithic 

 int implements have been found in the Peat Series, and are preserved in the Liver- 

 pool Museum. 



When the Lancashire Peat is followed into the valley of the Ribble it is found to 

 be continuous with the peat horizon found in the alluvium of the lowest alluvial 

 flat of that river. In other words, the valley of the Ribble at Preston had been 

 excavated as low as it is at present before the obstruction of drainage, which led 

 to the destruction of the forests in the plains and the consequent growth of thick 

 peat, the whole of which denudation took place after the deposition of the newest of 

 the Lancashire Glacial Deposits, the Upper Boulder-clay. The old river-terraces, 

 therefore, that fringe the sides of this valley are distinctly of post-Glacial age, 

 though of far greater antiquity than the lowest plain, which is the partial equiva- 

 lent to the peat of the plains. 



To sum up the total information obtainable in West Lancashire, it would appear 

 that after the deposition of the Upper Boulder-clay the Ribble gradually cut a 

 broad valley, a mile in width and 180 feet in depth, out of the Glacial Drift ; at the 

 same time the sea was denuding the western edge of the drift and wearing back 

 a lowland plain, on which afterwards grew a forest surrounding the whole of the 

 N. W. of England, the laud standing higher than at present ; after which the outfall 

 of the streams became obstructed and the growth of the peat ensued, which was 

 followed by a subsidence of some 70 feet or more, followed by the denudation of 

 coast-lines (still going on), the sequence being, commencing at the newest : — 



In the Plains. In the Ribble VaMey. 



Denudation Modern waste Waste of alluvial plain. "1 



Subsidence Tidal Alluvium Alluvial silt. 



( Obstruction of drainage . Peat. I Peat . bed> 



) Pause i orest | 



( Denudation j p^ 7 g ^ e ;;;;;.;} gwi. 



Older Denudations, &c. . . Nil Old Terraces. 



In the valley of the Irwell the work of excavation is also post-Glacial, and series of 

 old river-terraces occur ; and though no Palaeolithic implements have ever been found 

 in them, or in any stream north of the Mersey and the Ilumber, the author cannot 

 resist the conclusion, looking to the work of excavation done, that these terraces 

 are of the same geological age as those further south. 



On the Devonian System in England and in Belgium. 

 By Gr. Dewalque, For. Corr. G.S. 



Having surveyed, last year, the Devonian system of this country, I avail myself 

 of the Meeting of the British Association to offer a few remarks on the results of 

 my survey. As my visit was short I cannot lay claim to a minute aquaintance with 

 this great formation in England ; but as I am well acquainted with it in Belgium 

 and the Rhenish provinces, I hope the following remarks may prove of some interest 

 to geologists. 



A. I had not the time to visit South Devon. As regards North Devon my con- 

 clusions are as follows : — 



