LOWER AND UPPER GREENSAND OF THE SOUTH OF ENGLAND. 
419 
■ 
of the germs Jerea are occasionally met with, but the exact horizon in which they 
occur is not known, though 1 should judge from the character of the rock containing 
them that they belong to the horizon of the freestone beds.* 
Warminster, Wiltshire .—From the upper greensand strata of this locality entire 
forms of lithistid sponges have been met with in one or two limited areas, but they 
are of comparatively rare occurrence, and appear to be seldom found at the present 
time. On the other hand, beds of rock filled with the detached spicules of lithistid 
and tetractinellid sponges are exposed at Warminster itself, and in other places south 
of it, to beyond the village of Crockerton. The sponge-beds are largely worked for 
road material, and fragments of them are abundant on the surfaces of the fields, under 
which the beds crop out. 
The following section is shown in a quarry on the outskirts of Warminster : — 
( 1 -) 
( 2 -) 
(3.) 
( 4 .) 
(5.) 
(6.) 
( 7 .) 
( 8 .) 
( 9 .) 
feet, inches. 
Broken fragmentary chert in a marly matrix ... 3 0 
Greensand of quartz and glauconite grains ... 1 0 
Chert (sponge-bed).1 0 
Greensand similar to bed 2.1 0 
Siliceo-calcareous rock and chert, partly decomposed 
to a reddish loam (sponge-bed).2 3 
Greensand similar to bed 2.1 3 
Siliceous rock with chert (sponge-bed).2 6 
Greensand.1 0 
Siliceous rock with chert (sponge-bed) to bottom of 
quarry.1 3 
14 3 (=4-275 m.) 
Near Chute Farm, about four miles south of Warminster, another section is exposed 
as follows :— 
feet. feet. inch. 
(1.) Broken chert and siliceous rock.1 to 2 0 
(2.) Siliceo-calcareous rock and chert in beds of varying 
hardness (sponge-bed).10 0 
12 0 ( = 3’6 m.) 
* I noticed large masses of rock with some of these sponges weathered out on their surfaces on the 
heach about two miles west of Ventnor. From their appearance I could understand the origin of the 
remarkable figures of the tulip alcyonium given by Webster in ‘Transactions of the Geological Society,’ 
1814, vol. ii., p. 377, pi. 28. One need hardly say that the enormously long stems which are there 
represented as portions of the sponge have no real connection with it. These supposititious stems have 
been based on long cylindrical tubes with fluted walls, which interpenetrate the rocb. Whatever may 
he the true nature of these tubes it is certain that they are not the stems of sponges. 
