222 LIAS OF ENGLAND AND WALES: 
T. Beesley. Especially fine specimens of Cypricardia intermedia, 
Cardium truncatum, together with A. margaritatus, A. nitcsccns, 
Area Stricklandi, Gryphcea gigantea, and Avicula in&quivalvis, 
were procured from the hard band?. It was not possible to 
separate the specimens obtained from the zones of A. margari- 
tatus and A. capricornus, and Mr Beesley has given a joint list 
of species obtained from them.* (See p. 158.) 
The " Brown Hock/' as the Marlstone Kock-bed is sometimes 
called, is perhaps nowhere better developed than in the country 
around Banbury. It covers an extensive area to the north-west, 
forming a plateau that rises gradually from about 500 feet at 
Banbury to the escarpment of Edge Hill 710 feet high, and this 
area is intersected by several deep valleys. The high roads are 
broad, with grassy margins, the hedgerows are well timbered, 
while the ploughed fields display a rich brown soil. As remarked 
by Mr. Beesley, the disintegration of its friable stone has pro- 
duced the rich red land, so well adapted for wheat-growing, 
which Arthur Young has called the glory of Oxfordshire.! He 
adds that some of the beds yield nodules rich in phosphates, 
which doubtless contribute largely to the fertility of the soil. 
The rock is usually worked to a depth of from 5 to 14 feet. 
Its thickness at Banbury is estimated at 12 feet by Mr. Beesley, 
and it may be seen south-west of the town, north of Spring 
Cottage, where there is a deep excavation regarded as a natural 
cavern. The rock too has been quarried further north, and 
again near Dray ton. Its thickness at Hornton must be about 
30 feet, and at Swerford 20 feet, It is exposed at Great Tew, 
in road-cuttings at Broughton, west of Bloxham (see p. 269), and 
again east of Deddington. 
The Marlstone consists of more or less ferruginous and sandy 
limestone, the amount of sandy and calcareous matter being very 
variable. It is blue or greenish in colour where least exposed to 
the action of the weather, but otherwise presents various shades 
of brown. It is separated by partings of sandy loam or clay. 
The ferruginous matter, often of a concretionary nature and some- 
times iron-shot, varies considerably in different places, so that 
while at Adderbury and Kings Sulton the rock has become 
sufficiently charged with iron-ore to yield from 18 to 34 per cent, 
of metal, at Hornton and Edge Hill the stone furnishes a tough 
earthy limestone employed for building and paving. The greenish 
and brown varieties, often intermixed in edifices, form pleasing 
contrasts. Houses and walls in and around Banbury are largely 
constructed of the Marlstone, mostly of the brown rock whAch in 
appearance reminds one of the carstone or " gingerbread " stone of 
Hunstanton. In some places concretionary nodules impart a con- 
glomeratic aspect to the stone. I am informed by Mr. E. A. 
Walford that a bed of this nature occurs at the base of the Rock- 
* Proc. Geol. Assoc. vol. v. p. 181. 
"f Proc. Warwicksh. Field Club, 1872, p. 16; Young, Agriculture of Oxfordshire, 
1809, p. 5. 
