Geological Society of London. 419 



them to be satisfactorily determined. From its position and general 

 characters these beds were referred by the author to the Eed Crag, 



Discussion. — Mr. Prestwich said that he was quite prepared to accept Mr. 

 Whitaker's interpretation of the beds referred to the Thanet-sand. 



Rev. — Timins remarked that the presence of ironstone did not prove the beds 

 in which it occurs to belong to the Red Crag. 



Mr. Gwyn Jeffreys said that the Hmits of the Red Crag are not easy to de- 

 termine, and that the casts of the shells obtained in the beds near Sudbury are not 

 sufficient to prove the exact position to which they should be referred. 



Mr. Seeley stated that he had seen fine sections of Thanet-sands fully 20 feet 

 thick at Hagley. They contained sharks' teeth. The sands were capped with 

 pebbles, and above these with London-clay. The Woolwich-beds either thin out 

 to the north or ai^e changed to sands at Hagley. 



Mr. Charlesworth inquired as to the number of species that could be identified 

 with true Red Crag fossils. He thought that the presence of phosphatic nodules 

 was confirmatory of the beds, belonging to. either the Red or the Mammaliferous 

 Crag. 



Mr. Godwin-Austen remarked that the occurrence of Thanet-sands at Sudbury 

 was a fact of much geological interest. 



Prof. Ramsay considered that freshwater conditions generally succeed marine, 

 and that the submergence of the Chalk areas was followed by upheaval of land. 



Prof. Hughes thought that the base of the Thanet-sands could not represent a 

 land-surface, but that there had been land in. the neighbourhood which ga:ve rise 

 to fluviatile conditions. 



Mr. Whitaker, in reply, said; that he thought Mr. Seeley was mistaken in assert- 

 ing the occurrence of Thanet-beds at Hagley. He maintained that the balance of 

 probabilities was in favour of the beds referred by him to the Red Crag being of 

 that age rather than drift. 



2. "Notes on the Phenomena of the Qtiatemary Period in the 

 Isle of Portland and around Weymouth." By Joseph Prestwich, 

 Esq., F.E.S., r.€l>.S. 



The author remarked that although the physical features con- 

 nected with the later geological changes in thi& district were of much, 

 interest, they had hitherto attracted little attention. Commencing 

 with the oldest drift-beds, he showed that the remains of one, 

 formerly more extensive, had been found ia the Isle of Portland 

 at a height of 400 feet above the sea ; that it contained the remains 

 of the Elephas antiquus-, Equus fossilis, etc.; and that he found in. 

 this bed a number of pebbles of sandstone and ironstone of Tertiary 

 age, and of chert from the Greensands, whence he inferred that, as 

 such pebbles could not now pass over the plain of Weymouth, they 

 must have done so before that area was denuded, and when bridged 

 over by the Portland and Purbeck beds ; for the pebbles are derived 

 from beds which are only in situ to the north of the Weymouth 

 district, and at a distance of eight to ten miles from Portland. 

 Further, this transport must have taken place before the elevation of 

 the north end of Portland, and when the slope from the Bill to the 

 Eidgeway was uniform and gradual. The anticlinal line, which has 

 elevated the intermediate area, must be of later date than the drift- 

 bed. 



The author next proceeded to notice the raised beach at the Bill 

 of Portland, in which he had, with the assistance of Mr. Jeffreys, 

 determined 26 species of shells, two of them not now living in the 

 British Channel, and one new. This beach contains pebbles of the 

 Devonshire and Cornwall rocks. 



