742 J. W. JUDD ON THE SECONDARY ROCKS OF SCOTLAND. 



With regard to the origin of the New Red Sandstone, he would ask 

 whether the existing beds of rock-salt were consistent with deep- 

 sea formation. 



Prof. Hughes could not follow the author altogether in his con- 

 clusions as to the age of the present surface of the district described. 

 If the question was whether any part of the surface is now ap- 

 proximately the same as it was before the Pliocene period, he 

 thought that much might be learned from a consideration of the 

 plains of marine denudation which can be traced from districts in 

 the south, where there is some evidence as to their age ; and it 

 would appear that some of these are Precretaceous, the margin of 

 a lower plain being a shore-line along hills, the tops of which form 

 part of a higher and probably older plain. He thought the greater 

 part of the sculpturing should be referred to the period before the 

 Pliocene. 



Mr. Carrttthers stated that he had examined the exceedingly 

 interesting vegetable remains brought by Prof. Judd, and that their 

 nature left no doubt as to their truly belonging to the Coal- 

 measures. They belong to the Upper and Middle series. To him 

 this result had come quite unexpectedly. Could we also have 

 fossils from the later estuarine rocks, much light might be thrown 

 upon them. The Cretaceous fossils have Eocene affinities. 



Mr. Whitaker remarked that the Upper Estuarine beds were 

 described as being clays and sands, and inquired what evidence there 

 was of their being Cretaceous. May not some of them be Tertiary ? 

 The description of them is equally applicable to Tertiary and to 

 Cretaceous deposits. He further inquired whether the lavas cor- 

 respond with those on the north-east coasts of Ireland, and how 

 they lie on the beds under them, and to how great an extent were 

 the latter altered. How far do these Cretaceous beds answer to 

 those at Aix-la-Chapelle ? 



Mr. Woodward said that he saw M. Devey's collection at Aix-la- 

 Chapelle in April last, and that it contained many plants of Pliocene 

 age. He thought that the leaves in the specimens on the table had 

 a remarkably Eocene facies, and in this respect resembled those 

 found in America. He inquired whether Prof. Judd had observed 

 the lignite-beds in Antrim. 



Dr. Hicks stated that in the district particularly studied by him 

 he had found that great faults were very persistent through any 

 distances. 



Rev. J. P. Blake referred to the difference in character of the 

 rocks described from those of England. The Carboniferous beds 

 were formed in shallow water, near which there must have been high 

 land ; and this would have prevented the continuity of the several 

 deposits. The estuarine character was repeated in the Oolitic series 

 in Yorkshire, as also in the Lias. These deposits overspread large 

 areas, but were not continuous, and could not have been formed in 

 deep seas. So, too, with regard to the Chalk and Upper Greensand. 

 He inquired whether Chalk is a shallow- or a deep-sea formation. 

 He had always thought it was the latter ; but Dr. Gwyn Jeffreys had 





