136 Notices and Extracts from the Minutes of the Geological Society. 



Specimens which accompanied the preceding Letter 



Vegetable Mould 

 London Clay 



Plastic Clay Formation . <v 



At the depth of 



from to 2 feet. 



r Reddish-brown clay 2 to 34 



J Septarium 35 



1 Bivalve shells and pyritous wood, with Teredines . 70 to 90 



L Blue clay, somewhat sandy igO 



- Blue clay and broken shells, about 30 feet thick . . , 200 



Sandy blue clay 203 



Ash-coloured sandy clay 210 



Ash-coloured, yellow, and blue clay 215 



Blackish clay, with coaly matter 220 



Rounded flint pebbles 230 



Ash-colou red sand, above the hard. water spring . . . 235 



Mottled plastic clay 240 



Do. with soft chalky particles intermixed .... 242 



Do 246 



Red, green, and yellow mottled plastic clay .... 256 

 Green sand, with rounded carious flint pebbles . . . 260 

 A mixture of iron-pyrites and sand, very hard . . . 265 



r270 



Green sand -s 274 



V-278 

 Light-coloured sand, immediately above the spring •» 

 of soft water •» 



280 



