62 GEOLOGY OF THE ISLE OF WIGHT 



pretty shells of the smaller Barton types may be found, 

 with fragments of larger ones ; or a whole one may be 

 found. Owing to the cliff section cutting straight across 

 the strata, which are nearly vertical, there is far less of 

 the beds open to observation than at Barton, which 

 probably accounts for the list of fossils being much smaller. 

 The shells are chiefly several species of Pleurotoma, Rostel- 

 laria, Fusus, Voluta, Turritella, Natica, a small bivalve 

 Corbula pisuni, a tubular shell of a sand-boring mollusc 

 Dentalium, Ostrcea, Pecten, Cardium, Crassatella. ;The 

 fauna is like a blending of Malayan and New Zealand 

 forms of marine life. Throughout the Eocene from the 

 London clay onward the shells are such as abound in the 

 warm sea south east of Asia. Similarly the plant remains 

 take us into a tropic land, where fan palms and feather 

 palms overshadowed the country, trees of the tropics 

 mingling with trees we still find in more Northern latitudes. 

 The general character of the flora as of the shells was 

 Oriental and Malayan ; both being succeeded in later 

 strata by a flora and fauna with greater analogy to that 

 now existing in Western North America. 



In Alum Bay the Barton clay is suddenly succeeded 

 by the very fine yellow and white sands which run along 

 the western base of Headon Hill, the curve of the syncline 

 bringing them round from a nearly vertical to an almost 

 horizontal position. These are now known as the Barton 

 Sand. They are 90 ft. thick, the whole of the Barton 

 beds being 338 ft. in Alum Bay, 368 ft. in Whitecliff. 

 The sands were formerly extensively used for glass making. 

 They are almost unfossiliferous. The passage from Barton 

 clay to the sands in Whitecliff Bay is more gradual. The 

 sands here show some fine colouring which reminds us of 

 the more celebrated sands of Alum Bay. 



