122 THE AGE AND ORIGIN OF [May I907, 



"being in this sense of two different ages. It seems probable that 

 some of the more recent features of this type are only modifications 

 of older ones, and the working-out of their complete history will 

 require considerable time and the examination of a wide area. 



Mr. Clement Keid remarked on the difficulty encountered in dating 

 these plateaus, which were conspicuous features in the South-West 

 of England. The Torquay plateau might perhaps be as old as the 

 Cretaceous, for the overlap of the Cretaceous rocks is rapid, and the 

 Permian breccias have become very thin at Haldon. On the other 

 hand, the level of the plateau suggested that it might correspond 

 with the Pliocene plateau of Western Cornwall ; but there were no 

 deposits on it by which the date could be fixed. He agreed with 

 the Author as to the probable origin of the Bovey basin through a 

 synclinal flexure of Oligocene or Miocene date. The extensive 

 sheets of subangular Eocene gravel were difficult to understand ; 

 but he did not think that they were of marine origin. They were 

 often closely associated with pipe-clays and leaf-beds. 



Dr. A. E. Salter agreed with a previous speaker that the subject 

 treated of in the paper touched the fringe of a wider, and at 

 present but little understood, part of Geomorphology. The area 

 under consideration contained a high-level patch of gravel (The 

 Haldons) which had escaped the general denudation of the sur- 

 rounding country, owing to its porosity. After a steep slope, this 

 was followed by the plateaus described, which, since their forma- 

 tion, have been cut up by the more recent rivers. As similar 

 conditions may be observed in the Tertiary area of the Lower 

 Thames basin, in the Aldershot and Bagshot district, in the neigh- 

 bourhood of Goring Gap, in the southern part of Essex, and in the 

 northern part of Kent, the speaker thought that it was not necessary 

 to consider the phenomena observed in the Torquay area to be 

 of great geological age. He held that some widespread cause 

 must be looked for to explain them, and favoured Prof. Suess's 

 hypothesis, that the level of the ocean has diminished, as being one 

 factor in producing them. 



Mr. G. W. Lamplegh recalled the traces of a similar old plateau 

 in the South of Ireland, long ago recognized by Jukes. The con- 

 ditions described by the Author appeared to have affected the whole 

 south-western part of our islands ; and the investigation in this 

 particular area would therefore find wide application. 



Mr. 0. T. Jones remarked on the presence of a well-marked 

 plateau-feature in the South and South-West of Wales. The cliffs 

 of Southern Pembrokeshire rise abruptly to the plateau-level, which 

 is there about 200 feet. The planation for a few miles from the 

 coast has been very perfect ; but farther inland, as the level rises 

 slowly, the surface is slightly more uneven. The highest level 

 reached appears to be about 800 feet at the foot of the Prescelly 

 Mountains, which rise somewhat abruptly out of the plateau. 

 There is definite evidence in Southern Pembrokeshire of the plateau 

 having been overlain by Triassic sediments, which have penetrated 

 into cracks and fissures in the Carboniferous Limestone. The 



