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DR. G. J. HINDE ON BEDS OF SPONGE-REMAINS IN THE 
Though sponge-beds are abundant in the Haslemei’e district I have not met with a 
single specimen of an entire fossil sponge. The chert beds have been described by 
Dr. Fittojsi,'" but their organic nature does not appear to have been noticed. 
Midhurst and Petworth, Sussex. —In the lower greensand strata on the southern 
side of the Wealden anticlinal, about two and a half miles north of Midhurst, there 
are exposed several beds of hard siliceous rock, from eight inches to three feet in 
thickness (’2 to '9 in.), of a nearly similar character to the sponge-beds near Haslemere. 
The rock is of a yellowish tint, harsh to the touch and filled with minute cavities. 
The weathered, broken-up fragments which are plentifully distributed over the fields, 
clearly show that the beds consist of an aggregate of spicules resembling those in the 
Haslemere beds. Nearer Midhurst, and at a higher horizon, beds of porous siliceous 
rock, exhibiting numerous empty casts of spicules, are largely quarried for road 
materials. These beds consist partly also of sand grains which have been cemented 
together by the silica derived from the solution of the sponge-spicules, but the spicular 
casts are sufficiently numerous to show that sponges must have been very abundant. 
At Midhurst itself there are beds similarly filled with spicular casts and containing also 
glauconite grains which are cemented by a hard siliceous material. These beds are 
still higher in the series, and thus the presence of sponge-beds is shown throughout 
the lower or Hythe division of the lower greensand in this area. 
Near Petworth, about five miles east of Midhurst, sponge-beds from four to seven 
inches in thickness ('1 to ‘17 m.), are largely quarried for road material. The beds 
consist of an outer crust of porous siliceous rock with a central layer of very hard and 
brittle chert; which, according to Mr. Topley,! bears the local name of whinstone. 
The chert is filled with spicules, though they are only faintly shown. Both the 
spicules and the matrix exhibit, under crossed nicols, similar brilliant prismatic tints, 
indicating that their component silica is now approximately crystalline. 
Godaiming, Surrey. —On the surfaces of the fields on the summit of the plateau 
near this town there are frequently present small flat slabs or masses of hard, porous, 
siliceous rock, from three-quarters of an inch to four inches in thickness. The character 
of the rock resembles that of the sponge-beds of Haslemere, but the spicules have 
suffered greater alteration, and they do not weather out so clearly. They can, however, 
be recognised, not only in casts, but also as delicate white threads intercrossing each 
other on the weathered surfaces of the beds. Quartz-sand grains, and in some instances 
a reddish ferruginous material, are also included in the same siliceous cement with the 
spicules. These rock slabs are evidently portions of a continuous sponge-bed which 
have remained after the removal of the loose, incoherent sands which constitute the 
principal part of the strata immediately beneath the surface in this locality. 
Tilhurstow Hill. —To the south of the village of Godstone, Surrey, the beds of the 
Hythe division of the lower greensand are well exposed on the north slopes of the 
* “ Strata below the Chalk.” Trans. Geol. Soc., ser. 2, vol. iv., p. 147. 
t “ Geology of the Weald,” p. 125. 
