24 LONDON CLAY. 



LONDON CLAY. 

 Calcaire Grossier, &c., of Paris. 



1. Bagshot Sands, 2. London Clay, Bognor Beds. 

 3. Plastic Clay and Sands. 



The fluvio-marine deposits of the last section miglit have 

 been included under this division, as they evidently form 

 a continuation of the same series, and also belong to the 

 Eocene period. For the convenience of reference how- 

 ever, the list of fossils has been kept separate ; and under 

 this division, those beds belonging to the Bagshot Sand, 

 London and Plastic Clays, are associated. The Bagshot 

 Sands are extensively developed over Purbright, Primley, 

 and Woking Commons, and the adjacent country, con- 

 sisting of a series of loose sands, sandstone, greenish sandy 

 clay, and fissile marls, shales, &c., some of ihe beds, espe- 

 cially those composed of green sand and clays being more 

 fossUiferous, containing a few species of marine testacea, and 

 some interesting forms of fishes related to the Saw-fish, 

 Sharks, Eays, &c. : — Goldsworth hill, near Woking, aff"ords 

 a good section of these beds. The London Clay is a brown or 

 dark-blue, or blackish tenaceous clay, with layers at irregu- 

 lar depths of argillo-calcareous nodides, used for preparing 

 Roman Cement. Veins of gi*een sand, and masses of 

 sulphate of lime and ii"on pyrites also occur. The Bognor 

 beds, which are found towards the base of the London 

 Clay, consist of calcareous and siliceous nodules, or of 

 coarse green sand, or friable sand-rock with numerous 

 marine shells. In the Isle of Wight, the Bognor Beds 

 are a massive brown clay and clayey green sand, with 

 layers of iron sand and septaria. The beds usually termed 



