Geological Society of London. 89 



yegardccl those deposits as due to tho action of tho soa-waves 

 of tho lator or Middle TriaHsic pcriodH nj)f)n tho rocks of oUlor 

 Triassic (Biuitor) or l*ern»iau a<j;;o, (hirinj; tlio f^radiial olovation of 

 tho Luid, and as tlio probable roprcscntativ(3S in point of time of tlio 

 Muscholkjilk, otherwise deficient in liritain. 'J'ho author then 

 noticed tho influence of the conf^lomerato upon tho production of 

 certain niinerals, such as calamine and hoematitic iron-ores, and 

 discussed at some length the probable course of the phenomena of 

 denudation which furnished the materials for the formation of the 

 conglomerate at different levels, in which ho recognized two great 

 periods of oscillation, the first witnessing a downward movement of 

 the Pala30zoic lands, and lasting throughout the de])Osition of the 

 New Ked Marl and Sands, and the second, during which the accu- 

 mulations of the former were again, at least partly, denuded. With 

 regard to the time at which the remains of Thecodont reptiles were 

 imbedded in the conglomerate, the author inferred from the evidence 

 that this took place late in the period of the Keuper. 



Discussion. — The President inquired on what ground the author considered 

 these reptiles to belong to a late looriod in the Keuper, and -was informed that the 

 author spoke especially with relation to the Keuper of the Bristol area, of which 

 the beds containing them occupied the highest position. 



Prof. Ramsay considered these conglomerates not merely as of marine origin, 

 but as breccias which had covered the old land surface which had been worked up 

 by the water of the New Red Period. He objected to the term Sea having been 

 introduced into the paper, as, though the tracts may have been islands and 

 promontories, and though the water which surrounded them was salt, there wa» no 

 open sea, but merely a large inland salt-lake, in which the New Red Marl was 

 formed. The marl was less connected with the New Red Sandstone than with the 

 Lias. The Muschelkalk being absent, it was constantly the case that the marl 

 rested immediately on the palaeozoic rocks without the intervention of the Bunter 

 Sandstone. He thought that there were good grounds for connecting the Rhsetic 

 beds with the New Red Marl below and the Lias above. The probability was that 

 the change in character was due to a gradual influx of the sea into the inland lakes. 

 He thought that the Thecodont Saurians might also eventually be found even in 

 beds of Liassic age. 



Prof. T. Rupert Jones remarked that Mr. Tawney and Dr. Duncan had already 

 intimated the St.-Cassian aspect and character of the Sutton beds. The freshwater 

 character of some of the Keuper beds was, he remarked, indicated by the presence 

 of Estherioe ; and he alluded to the fact of the Bristol paljeosaurians having been 

 erroneously used as Permian characteristics in Russia and Carolina. 



Mr. W. Boyd Dawkins had found at Cheddar that the Dolomitic conglomerate 

 formed two great tongues running up ravines in the older rocks, which had probably 

 been due to subaerial action. 



Prof. Morris alluded to some sections which seemed to corroborate the views of 

 Mr. Etheridge, and pointed out the relation of the conglomerate beds to the over- 

 lying strata at those points. He also mentioned certain peculiarities in the structure 

 of the conglomerate itself. 



Mr. Etheridge stated in reply that the Marls in the Bristol area were the 

 exception, the greater part of the New Red beds being sandstone. 



2. " On the Superficial Deposits of portions of the Avon and 

 Severn Valleys and adjoining Districts." By T. G. B. Lloyd, Esq., 

 C.E., F.G.S. 



The author, after describing the general characters of what he 

 termed the Drifts of the Upper and Lower series, and the fresh- 

 water gravels of the Lower Avon, comprised within the district 



