214 Lower Greensand. 



are scattered through the clay, including the well- 

 known Perna Mulleti, Trigonia caudata, Gervillia 

 aviculoides, Areas, Pectens, Oysters, Rostellaria Par- 

 kinsoni, and Hemicardium Austeni, &c. &c. 



THE LOWER G-KEENSAND, of which the Atherfield Clay 

 is a subdivision, comes next in succession, in the Isle 

 of Wight, beginning with a bed of sandstone containing 

 Gryphcea sinuata and many other shells, succeeded by 

 29 feet of clay, vulgarly called the 'lobster bed,' from 

 the presence of Meyeria magna, formerly called 

 Astacus, together with Ammonites Deshayesii, &c., 

 overlaid by nodular bands with Gervillia aviculoides, 

 &c., above which, clay is repeated, with the same 

 Meyeria. Above this, sands and clays alternate to the 

 top of the series, with many fossils, among which may 

 be mentioned as characteristic, Terebratula sella, T. 

 Gibbsii, T. biplicata, Limas, Gryphceas, Gervillia 

 solenoides, Ammonites, Nautili, and other remarkable 

 Cephalopoda of the genera Crioceras, Ancyloceras, 

 and Hamites. The whole of these strata overlying 

 the Wealden beds occur in magnificent sections along 

 the southern cliffs of the Isle of Wight, dipping north- 

 erly under the Gault, Upper Greensand, and Chalk, 

 which in a high ridge stretches across the island from 

 Culver Cliff to Alum Bay. Overlaid by the Gault, and 

 reposing on the Weald Clay, the Lower Green sand also 

 sweeps round the whole Wealden area from Sand gate to 

 Guildford and Haslemere, and from thence to the coast 

 north of Beachy Head. Between Guildford and Hasle- 

 mere it forms high scarped terraces. The sands are 

 sometimes quite soft, with intercalated hard bands, and 

 they are frequently ferruginous. A good building 

 stone, very fossiliferous, being sometimes an impure 

 limestone, called the Kentish rag, lies in the lower part 



