ing made to
co-ordinate the English with the continental Corallian.

The Corallian rocks are nowhere better displayed than in the cliffs at
Weymouth. Here Messrs Blake and Huddleston recognized the following
beds:--

/ Upper Coral Rag and Abbotsbury Iron Ore.
| Sandsfoot Grits.
Upper | Sandsfoot Clay.
Corallian < Sandsfoot Clay.
| Trigonia Beds.
\ Osmington Oolite (quarried at Marnhull and Todbere).

/ Bencliff Grits.
Lower | Nothe Clay.
Corallian < Nothe Clay.
\ Nothe Grit.

In Dorsetshire the Corallian rocks are 200 ft. thick, in Wiltshire 100
ft., but N.E. of Oxford they are represented mainly by clays, and the
series is much thinner. (At Upware, the "Upware limestone" is the only
known occurrence of beds that correspond in character with the Coralline
oolite between Wiltshire and Yorkshire). In Yorkshire, however, the hard
rocky beds come on again in full force. They appear once more at Brora
in Sutherlandshire. Corallian strata have been proved by boring in
Sussex (241 ft.). In Huntingdon, Bedfordshire, parts of Buckinghamshire,
Cambridgeshire and Lincolnshire the Corallian series is represented by
the "Ampthill Clay," which has also been called "Bluntesham" or
"Tetworth" Clay. Here and there in this district hard calcareous
inconstant beds appear, such as the Elsworth rock, St Ives rock and
Boxworth rock.

In Yorkshire the Corallian rocks differ in many respects from their
southern equivalents. They are subdivided as follows:--

/ Upper Calcareous Grit \
Kimeridge | / Coral Rag and Upper >_A. plicatilis._
Clay | | Limestone |
Cora- |"Coralline | Middle Calcareous Grit /
....... llian < Oolite" <
Rock | | Lower Limestone \
Oxford | \ Passage Beds >_A. perarmatus._
Clay \ Lower Calcareous Grit /

These rocks play an important part in the formation of the Vale of
Pickering, and the Hambleton and Howardian Hills; they are well exposed
in Gristhorpe Bay.

The passage beds, highly siliceous, flaggy limestones, are known locally
as "Greystone" or "Wall stones"; some portions of these beds have
resisted the weathering agencies and stand up prominently on the
moors--such are the "Bridestones." Cement stone beds oc