LOWER AND UPPER GREENSAND OF THE SOUTH OF ENGLAND. 417 
Eastbourne and Folkestone. — According to the Geological Survey Memoir, # the 
characteristic malm does not extend round the south-western margin of the Weald, 
but gradually disappears to the east of Steyning, in Sussex, and the upper greensand 
is represented by beds of sandy marl which extend as far as Eastbourne. In these 
beds I have not discovered any sponge-remains, but in some higher beds of dark 
grayish glauconitic sandstones, belonging to the horizon of the chloritic marl or the 
base of the chalk marl, there is a very characteristic sponge-fauna, which differs so 
greatly from that of the upper greensand proper that it merits notice, although 
beyond the limit assigned to my paper. These sponge-beds, or reefs, as they are 
termed by Mr. Price,! appear to consist exclusively of entire examples of hexactinellid 
sponges belonging to the genera Flocoscyphia, Craticularia, and Stauronema, growing 
together in such abundance that the exposed rock surface is covered with them. 
These and similar sponges are either wholly absent from the sponge-beds of the lower 
and upper greensand or represented by mere microscopic fragments of their skeletal 
mesh, and their presence in these deposits may be regarded as indicating the existence 
of different conditions, in which deeper water prevailed than when the greensand 
sponge-beds were formed. 
Shanklin, Ventnor, and the Undercliff, Isle of Wight. —The sponge-beds in the 
upper greensand of these places principally occur in the upper division, characterised 
by bands of chert and siliceo-calcareous rock. The beds are well shown in the 
quarries near Shanklin and at Ventnor, and along the Undercliff. The striking 
parallel bands of cherty rock which project in relief in the upper portion of the cliff, 
and the huge masses of the same material scattered over the terraces beneath, consist 
of sponge-beds. At the Hail way Station at Ventnor the following section is exposed; 
the bed marked 1 is immediately overlaid by the chloritic marl. 
feet, inches. 
(1.) Sificeo-calcareous rock, with bands of chert (sponge- 
bed) .21 0 
(2.) Siliceo-calcareous rock. 4 0 
(3.) Building stone with nodular layer of bluish lime¬ 
stone . 1 7 
(4.) Freestone of quartz-sand, glauconite, and mica 
cemented by calcite.3 2 
(5.) Freestone, similar to above, but with some silica in 
cementing material .4 10 
( 6 .) Beds of siliceo-calcareous nodules with chert 1 4 
(7.) Freestone of similar character to bed 5 . 4 9 
(8.) Hard siliceo-calcareous rock, with chert .... 1 0 
(9.) Freestone resembling bed 5. 3 0 
(10.) Freestone and cbert to base of quarry. 3 0 
47 8 (=14-3 m.) 
* “ Geology of the Weald,” p. 158. f Quart. Journ. Geol. Soc., vol. xxxiii., p. 435. 
