634 



MESSES. GARDNER, KEEPING. AND MONCKTON ON THE 



Discussion. 



The President referred to the numerous communications to the 

 Society relative to the Eocenes of Hampshire, and complimented 

 Mr. Gardner on being able to say something new. 



Mr. Whitaker observed that in point of fact but little had been 

 written about the Barton Beds of Barton Cliff, attention having been 

 mostly drawn to the Headon Series. He spoke of Mr. Trimmer's 

 section, 20 in. to 1 mile, executed in 1849 ; there was also one at 

 Southampton by Mr. Keeping. The Barton section had hitlierto 

 been difficult of access. 



Commenting on the cliff-section, he regarded the whole as one 

 great series ; there were no great gaps in the succession, the changes 

 being local only. There was some difference of opinion as to the base- 

 line of the Headon Series. The sandy beds below constitute a large 

 portion of the material coloured as Upper Bagshot. In this occurs a 

 clay bed, which he regarded as exceptionally intercalated ; do the 

 fossils connect it with the Barton Series ? There was no gap of 

 importance between the Barton and Bracklesham Series. The 

 pebble-bed was exceptional in containing some subangular flints and 

 quartz. The oscillations in the area had not been of great import- 

 ance. He thanked Mr. Gardner for the care he had taken over the 

 lists of fossils. 



Mr. Irving recognized a general resemblance to the beds of the 

 London basin, the changes of level being chiefly local. He would 

 like to know if the fauna discovered by Mr. Monckton in the sandy 

 Upper Bagshots occurred in exceptionally argillaceous beds. 



Mr. MoNCKioN remarked that this bed was quite as sandy as the 

 others. 



Mr. Irving expressed his doubts as to the possibility of specific 

 identification of these fossils. Such a large number of genera were 

 common to the two divisions, that he doubted any great difference 

 in the fauna of the Upper and Middle Bagshots. 



Mr. Herries said that the Pebble-bed was a convenient line of 

 separation between the Upper and Middle Bagshots of the London 

 basin, though perhaps at a lower horizon than the division-line 

 in the Hampshire area. He assured Mr. Irving that in the 

 London basin the fossils of the " green earths " (Middle Bagshots) 

 were quite distinct from those in " Tunnel Hill " (Upper Bagshots), 

 in which he believed only one purely Bracklesham form had been 

 found, and of that but a single specimen. 



Mr. Gardner had no desire to favour either the Headon or the 

 Barton Series. He placed the upper boundary of the latter where 

 the marine shells cease. The sands, therefore, to which Mr. 

 Whitaker alluded belonged to the Barton Series. The lower 

 boundary of that series was pretty distinct, though at Selsey the 

 beds shade into each other. But the subtropical forms do not occur 

 above the ISTummulite-zone. Above this the fauna is of a more 

 temperate character, with a partial recurrence of London-Clay forms. 

 The upper beds in the section were far above the Upper Bagshots 



