110 PROF. J. PRESTWICH ON THE COEEELATION OF THE 



and out of chaos evolved order. Whilst some of us knew a limited 

 district or certain beds, the knowledge of Prof. Prestwich was not 

 only detailed, but also general. He himself would confine his re- 

 marks to the beds between the Chalk and the London Clay. There 

 had been a difference in their views about certain pebble-beds in 

 a limited district. His business, as a Surveyor, had been to map 

 beds that could be mapped, and when he found miles of pebble- 

 beds without a break, some without fossils, others with calcareous 

 matter and fossils, he had thought that the fossiliferous character 

 might be a matter of accident, and that elsewhere the fossils might 

 have been dissolved out where not protected. The Author would 

 admit that a certain degree of community in the fossils rendered 

 the palseontological test somewhat uncertain. He thought that 

 eastward of Faversham only the lower part of the "Woolwich Beds 

 was represented. The term Easement-bed might seem to show 

 that these beds formed part of the London-Clay series, which in 

 great part they did not ; hence a local name such as Oldhaven Beds 

 was suitable, though for the neighbourhood of London the name of 

 "Blackheath Beds" was better. 



Dr. Evans had some acquaintance with the Eocenes of the neigh- 

 bouring continental areas, and the correlation of our English beds 

 with these was one of great interest. He thought that the transfer 

 of the Sands of Bracheux from the horizon of the Thanet Sands to 

 that of the Woolwich and Reading series would be universally 

 accepted. These questions must be decided mainly on palseontolo- 

 gical evidence. There were three main points in the paper : the 

 transfer of the Upper Bagshots to the Brackleshams, the closer 

 union of the Lower Bagshots with the London Clay, and the transfer, 

 to which he had already alluded, of the Sables inferieurs of the 

 Soissonnais, &c. to the horizon of the Woolwich and Reading series. 

 He thought that the Author's conclusions would, in the main, be 

 generally received. 



Dr. Geikie said that he had no practical acquaintance with the 

 ground himself, but he was glad of the opportunity of acknowledging 

 the obligations the Geological Survey had had to Prof. Prestwich, 

 of the value of whose work he had himself the highest appreciation. 



Mr. Irving was afraid lest he might anticipate the contents of a 

 paper shortly to be read before the Society. There might be a 

 closer connexion between the Lower Bagshots and London Clay 

 than had been hitherto recognized, in spite of attenuation and local 

 erosion and unconformities on the north side of the basin. He 

 fully recognized the subordination of local details to data covering 

 a wider range in such a question as this. 



Mr. G. r. Harris thought that some allusion might have been made 

 to the " Tufeau de Ciply." He questioned whether the table repre- 

 sented the present classification. He thought the Lower Landenian 

 should be placed higher than the Thanet Sands. As to the greater 

 part of the Upper Landenian in Belgium, it was very doubtful what 

 they represent, and the same thing might be said of the almost un- 

 fossiliferous division of the Ypresian. 



