97 
hills along the escarpment in the vicinity of Stroud, and con- 
tains all the beds seen in the Cleeve and Leckhampton Sections 
except the Lower Trigonia Grit and some other minor beds 
which Dr Wright has placed in the Humphriesianus zone. I 
have therefore selected this hill to continue the sequence, and 
to show in our proceedings the changes which occur in the beds 
of the Inferior Oolite in their south-west extension. 
Selsley hill is almost isolated from the mainland of the 
Cotteswolds. A narrow neck of land at the south-west end 
alone connects it with the ridge which we know as Longwood, 
Frocester hill and Uleybury. Excavations have been made in 
numerous places on its slopes, so that a fairly complete general 
Section can be constructed. 
The base of the hill consists of shaley clay of the Middle 
Lias, with the Marlstone above it. There are exposures of 
these beds in the Railway cuttings in the Nailsworth valley, 
at Woodchester, Lightpill and Dudbridge, but a better expo- 
sure is on the Rodborough side of the stream at Dudbridge, 
where the beds are extensively worked for brick-earth. The 
Marlstone differs from the beds near Dursley, at Churchdown, 
and in the northern Cotteswolds. It consists of several feet 
of rather soft Sandstone, and one or two beds formed of 
hard concretionary blocks, brown and soft on the surface, 
blue and hard internally, and occasionally fossiliferous. The 
fossils are of the genera and species usually found in the 
Marlstone ; Ammonites Margaritatus is rather common, but not ~ 
well preserved. The spinatus beds are not exposed on the 
Selsley side of the valley, but are seen in one of the Dudbridge 
brick-pits. The same remark applies to the Upper Lias, for 
although there are brick-pits at Dudbridge, Cainscross, and near 
Ebley, they are all on the opposite side of the stream, and there 
are none on the Selsley side; in consequence the thickness of 
these beds can only be approximately stated, but as the spring 
in the highest well in the slope of the hill at Selsley is 400 feet 
above sea level, the Upper and Middle Lias together must 
be nearly 300 feet thick above the bed of the Frome at Dud- 
bridge, which is about 100 feet above sea level. 
H 
