346 MR. C. EEID ON THE TLEISTOCENE 



the lower red gravel /, and lies below the marine strata with southern 

 shells, instead of above them. It will be observed that Godwin- 

 Austen nowhere says that he has seen the complete section as shown 

 in his figure ; it is only given as a diagram to explain the general 

 relations of the deposits. However, this paper by Godwin-Austen 

 is by far the most important contribution to the Pleistocene geology 

 of the Sussex coast. 



The next important memoir relating to the district was read 

 before this Society in 1858 by Prof. Prestwich,^ who traced the 

 Raised Beach of Brighton westward to near Arundel and Goodwood, 

 and recorded several species of marine fossils from the latter place. 

 West of Goodwood he found unfossiliferous gravels, probably of the 

 same age, at Bourne Common, around Portsmouth, and in the Isle of 

 Wight. In a later paper ^ Prof. Prestwich announced the discovery 

 of a similar raised beach at Portsdown Hill, at a height of 125 

 feet. The work of the Survey having thoroughly corroborated Prof. 

 Prestwich's view that these deposits all belong to one period, there 

 will be no occasion here to discuss the question. 



Mr. A. Bell in 1871 published an account of the mud -deposit at 

 Thorn ey, near Selsey,^ and this was reprinted, with additions, in the 

 second edition of Dixon's ' Geology of Sussex.' 



That edition also contained a note by Mr. E. H. Willett on the 

 discovery of a Palaeolithic implement at a depth of fifteen feet in 

 the Coombe Rock (p. 112) ; and another by Mr. H. Willett on 

 bones and freshwater shells discovered " near East Wittering in a 

 deposit beneath the glacial beds of Selsey " (p. 19). The note 

 by Mr. H. Willett probably refers to the deposit at West Wittering 

 described below. 



The general state of opinion as to the succession of the Pleistocene 

 deposits of the Sussex coast at the time when the Drift Survey was 

 commenced (in 1884) may therefore be thus summarized : — It 

 was generally recognized that an old sea-beach lay beneath the 

 irregular chalky deposit known as the Coombe Rock. This later 

 gravel was commonly considered to indicate a period of excessive 

 rainfall. The fossiliferous strata at Selsey, with southern mollusca, 

 were believed to underlie a glacial deposit with eriatic blocks. 



The study of the geology of the Sussex Levels has proved to be a 

 task of considerable difficulty, ai I even a long residence in the 

 district left many points in doubt. It is only by the aid of the clear 

 sections exhibited during the long-continued south-westerly gales of 

 the past autumn and winter that I have been able satisfactorily to 

 examine the area in Selsey Bill which may be regarded as furnishing 

 the key to the whole district. The points to which my attention 

 has been more especially directed w^ere : 1st, the origin of the wide- 

 spread de]iosit known as the Coombe Rock ; 2nd, the succession of 

 the Pleistocene strata ; 3rd, the source from which the erratic blocks 



1 Quart. Journ. Geol. Soc. vol. xv. (1859) p. 215. 



2 Ihkl. Yol. xxviii. (1872) p. 38. 



^ Ann. Mag. Nat. Hist. ser. 4, vol. viii. p. 45. 



