46 
THE GEOLOGIST. 
capping the higher groimd, eapecially near Burford, Northleach, &c. 
In some respects it differs lithologically from the same Formation on 
Minchinhampton Common, and it is thicker in its extension eastwards. 
The top strata usually consist of beds of marl, which are more or less 
fossiliferous ; and the lower of white limestones, which are extensively 
quarried near Sherborne Park, above Burford : and, according to Mr. 
Hull, these limestones contain more fossils at a quarry where the 
Oxford and Shilton roads join, than anywhere else. Near Andoversford, 
about seven or eight miles east of Cheltenham, many fossils may also 
be procured in beds of rubbly, white Oolite. The usual fossils are 
shells and corals, belonging, however, to comparatively few genera, 
and presenting in this respect a strong contrast to the Great Oolite on 
the south. 
The Forest Marble appears at Coin Uogers and near Aldsworth, 
about six miles south-east of Northleach, as well as near Burford, and 
the Cornbrash also near Shilton. "We merely, however, mention this 
in case the student should like to compare them with their equivalents 
near Cirencester ; for it often happens that even within a very few miles 
the divisions and sub- divisions of any given Formation present striking 
lithological differences — certain beds coming in, and others thinning 
out, which it is always necessary to note carefully, and which can only 
be done by a minute and accurate examination of every available section, 
and a close comparison of the zoological contents of each stratum.* 
There is another and very important member of the Great Oolite with 
which it is intimately connected, and of which it forms an integral 
part, viz., the Stonesfield slate, to which we must now turn our 
attention. It forms the lower division of this Formation, and consists 
of a coarse, brown, fissile, ragstone, sometimes sandy and slaty, or 
passing into a shelly, oolitic freestone ; and these characters are very 
variable over a considerable area in the Cotswolds. Formerly, there 
were several quarries worked at Sevenhampton Common, five miles east 
of Cheltenham, and are even now well worth a visit. The ragstone, 
which is a more compact slaty stone, often blue in the centre, is there 
» We advice the student to get Mr. Hull's valuable and interesting memoir on 
"The Geology of the Country round Cheltenham," published by the Geological 
Survey, price 2s. 6d., where detailed sections are given, with copious lists of fossils, 
and ample details of every spot worth visiting. 
