109 
and Dorset railway, the road has been carried under the line by 
_ means of a cutting, which gives a useful section of the strata in 
that locality. 
The Rhetic White Lias, the Black Marl beneath it, the 
- Rhetic bone bed, and the Blue and Grey Marls which underlie 
: it are all exposed, after which the road cutting passes into the 
-Keuper Marls which are here of considerable thickness, and rest 
ona base of Conglomerate of the same age. If measurements 
had been taken when the cutting was in progress, a very complete 
_ section might have been obtained here, but as it is, the general 
4 arrangement of the beds can be clearly traced, and the bone bed, 
_ which is only a few inches in thickness, literally teems with 
organic remains. 
The writer would advise all Geologists visiting the locality, to. 
see this section. 
GURNEY SLADE, 
__ Proceeding onwards in the direction of Gurney Slade. the 
- Mountain Limestone is very soon met with, and, in a large quarry 
before entering the village, there occurs one of the finest examples 
of the Liassic Dykes, which are so marked a feature in the 
geology of these hills. The material of the Dyke being useless 
for any industrial purpose, the Mountain Limestone has been 
‘quarried away on each side of it, leaving it standing like an 
immense natural wall which the advancing excavations of the 
« uarry have left behind. 
point, and it varies in thickness from 4 to 6 feet. The Dyke con- 
sists of vertical bands of various substances, chiefly of a yellow 
wssic appearance, intermixed with belts of spar, which are in 
ked contrast to the dark blue rocks of the Mountain Lime- 
e by which the Dyke is surrounded; and the presence of 
