BRODIE — GEOLOGY OF GLOUCESTERSHIRE. 
87 
ness at Leckhampton, may be studied to advantage at Crickley Hill be- 
tween Cheltenham and Birdlip, at Haresfield, Frocester, and Nailswcrth. 
Below the " Pisolite " at Crickley is a band of brown, shelly limestone, 
containing many Ammonites and Belemnites, and a peculiar Tere- 
bratula (T. cynocephala), which is highly characteristic of this zone. 
This limestone has been perforated by boring shells, and minute frag- 
ments of bones and teeth of fish are irregularly dispersed through it, so 
as to form a kind of bone-bed. At Leckhampton, with the inter- 
vention only of a few inches of red sandy marl, it reposes on the 
blue shale of the Upper Lias. At Haresfield and Frocester the 
basement beds are much thicker and more fossiliferous, and overlie a 
thick stratum of yellow micaceous sand, from 40 to 60 feet thick, 
below which the grey marls of the Upper Lias appear. Numerous 
species of ammonites, belemnites, and other shells, both univalves and 
bivalves, have been discovered at both these places. The " Ammonite 
bed" there is a coarse brown oolitic sandstone, more or less ferruginous. 
Although it would be quite out of place in an article like the present 
to enlarge upon a disputed point as to the true relations of these beds, 
it is only right to mention that, while some geologists class them with 
the Upper Lias, others retain them in the Inferior Oolite. Probably the 
truth lies between the two opinions, and this stage will be found to be 
really intermediate. At any rate, for the present it must be left an 
open question, until we obtain further knowledge of the fossils of these 
deposits in other districts, and are thus able to weigh the evidence in 
full, and arrive at exactitude. 
Viewed from the valley, the outer chain of the Cotswold hills pre- 
sents a bold line of escarpment, varying in height from 900 to upwards 
of 1000 feet above the level of the sea. The lower portions present 
grassy slopes, sinking gently into the plain below, and the upper 
stand out as bold mural cliffs, for many miles in extent. The hills are 
often well wooded even to their summits, and their tortuous course 
from N.E. to S.W. is marked by projecting headlands and deeply- 
indented bays. There can be no doubt, indeed, that at some remote 
period the sea occupied this now rich and fertile valley ; and there is 
evidence in certain drift deposits and ancient shingle beaches at various 
heights along these hills, to show they were once of much less 
elevation, and washed by the waves of an ancient inland sea, not inaptly 
termed the Straits of Malvern. 
