56 



ON THE CONCHOLOGICAL FEATURES OF THE LENHAM 



SANDSTONES OF KENT 



AND THEIR STRATIGRAPHICAL IMPORTANCE. 



( Prefidcnlial Address delivered al the Aiiiuial Meeling, October i6tli, 1915). 



IJy R. KULLEN NEWTON, K.(;.S.,i 



OK THK BurilSH MUSKUM. 



PlA'IKS I — 4. 



InTRODUC'J'IOX. 

 BiHlJOC.RAPHY. 



List of 'I'hk Concholo(;ical Detek'NIinations. 

 Distribution Tabi.k. 

 c0nct,u.si0ns. 

 Explanation of Plates. 



IXDKX. 



Introduction. 



At various points along the summit of the chalk escarpment forming 

 the North Downs of Kent and Surrey and extending from Paddles- 

 worth near Folkestone to Lenham near Maidstone, and thence to 

 Netley Heath between Guildford and Dorking — a distance east and 

 west of about seventy miles — there occur in pockets, cavities, or 

 "pipes" of the chalk formation, certain scattered masses of a reddish 

 ferruginous sandstone at considerable altitudes above sea-level ; at 

 Paddlesworth this sandstone has been observed at 600 feet ; at 

 Lenham 680 feet : while at Netley Heath it is found at a height of 

 between 570 and 600 feet. Sandstones of corresponding age are met 

 with in France particularly on the hills between Calais and Boulogne, 

 and on Cassel Hill near Dunkirk at 515 feet ; they also occur at 

 Lou vain (200 foet) and Diest, both in Belgium, the beds of the latter 

 locality having yielded fossiliferous remains bearing a resemblance to 

 the Lenham fauna, although often differing in specific characters. 



The more important of these sandstone deposits, so far as this 

 country is concerned, are those found on the Lenham Downs, as they 

 contain the remains of a marine fauna, chiefly of conchological 

 interest, whereas the beds of other districts are generally unfossilifer- 

 ous, although it should be mentioned that a few moUusca of rather 

 uncertain character have been obtained from both Paddlesworth and 

 Netley Heath. 



I Publislicd by periiiission of the Trustees ol" the liritish Museum. 



