478 PKOCEEDINGS OF THE GEOLOGICAL SOCIETY. [JunO 3, 



with pieces of chert lying about. This I take to be Lower Green- 

 sand (see fig. 3). 



Samer rests on Wealden beds : light-coloured, whitish, and yellow 

 sand, with some pebbles and mottled clay ; and in places between 

 here and Desvres, sands (sometimes ferruginous) and mottled clays 

 are seen. 



Some very interesting sections are exposed near Equihen and St. 

 Etienne-au-mont, three or four miles south of Boulogne. The hill 

 above Equihen is capped by Wealden beds, with a slight covering 

 of loam and subangular flint-gravel. The different sections here 

 are as various in character as elsewhere. One pit gave : — 



Blown sand. 



Whitish sandy clay, with sandy ironstone, 6 feet. 



Hard concretionary sandstone, very ferruginous, 3 to 4 feet. 



Yellowish clay and concretionary clay-ironstone. 



another section was as follows : — 



Sandy flint-gravel. 



Loose pebblefe, with 1 inch of pipe-clay near the bottom, 6 to 8 feet. 



Sand and coloured clay (white, yellow, blue, and sometimes black, with 



vegetable markings ?), 5 or 6 feet. 

 Ironstone. 



i^car the church of St. Etienne are many sections, some of which 

 Lave been very minutely measured by MM. Sauvage and Hamy*. 

 As no two pits are alike, nor any one pit regular in all its parts, I 

 have not attempted any such accuracy. I give two or three examples. 

 Just south of the church : — 



Dirty loam and loose pebbles, to 3 feet. 

 Pebbles, 6 feet. 



Bluish clayey sand, 1 to 6 inches. 

 Yellow sand and sandstone, 4 feet. 



A second pit further east showed a few thin layers of hard ferru- 

 ginous sandstone with the pebbles. 



A third pit south-east of the church : — 



Interstratified sand and small pebbles false-bedded, particularly near the 



top, 15 feet. 

 Yellow and white sand. 

 Grreen clay and ironstone. 



Other pits towards the southern part of this outlier show good 

 sections of the pebble-beds. In one case they are divided by five feet 

 of sandy clay : — 



Pebbles, 2 feet. 



Whitish sandy clay, 5 feet. 



Pebbles, 5 feet. 



AroTind Boulogne all the heights are occupied by "Wealden beds. 

 In the new railway- cutting at Honvault, a fault brings Wealden 



* Terr. Quatern. des Boulonnais, p. 7 ; see also Eigaux, " Notice Stratigra- 

 phique sur le Bas-Boulonnais," Bull. Soc. Academique de Boulogne, 1865. 



