238 
LIAS OF ENGLAND AND WALES : 
This pit afforded a very interesting series of beautifully pre- 
served fossils., which are enumerated in the following list : 
Cardium truncatum. 
Hippopodium ponderosum. 
Modiola scalprum (very abundant). 
Pholadomya decorata. 
ambigua. 
Pleuromya costata. 
Serpula. 
Pentacrinus. 
Ammonites margaritatus (very 
abundant; many of the speci- 
mens attaining a great size). 
norrnanianus. 
Belemnites elongatus. 
Cryptaenia expansa. 
Ostrea. 
Pecten sequivalvis. 
Avicula in sequivalvis. 
From Pick well to Whissendine the Marlstone is concealed by 
Drift, but further on it has been exposed by Ashwell station, and 
has been quarried in several places in the Vale of Catmos, near 
Langham and Oakham, where its thickness varies from 6 to 
18 feet. The beds below the Rock-bed, consisting of shaly 
micaceous clays, with bands of sandy rock, have been worked 
for brickmaking near Oakham. 
A boring at Hambleton south-east of Oakham proved 15 feet 
of the Marlstone ; and a shaft sunk one mile west of Oakham 
proved the following beds : * 
FT. 
Drift - - - - - .4 
Upper Lias - - - - - - 30 
Middle /Rock-bed - . .18 
Lias \Sands - - - - 28 
80 
"Brown Rock," quarried near Braunston, S.W. of Oakham 
Station, has been used for old buildings and some modern 
buildings in Oakham ; the new houses however are now mostly 
constructed with red brick. The rock is also quarried near 
Laund Abbey. 
Northward from Ashwell the Rock-bed of the Marlstone forms 
a fine escarpment about the villages of Teigh, Edmondthorpe, and 
Wymondham. In cuttings of the Bourn and Saxby railway, 
north- west of Wymondham the Marlstone was exposed to a depth 
of 6 or 7 feet beneath the Upper Lias. The rock consists of 
brown ferruginous sandy limestone with greenish cores : here and 
there it contains seams of good ironstone, but it is mostly of poor 
quality. Clusters of Rhynchonella tetrahedra occur, and Tere- 
bratula punctata and Belemnites may also be found. A number 
of small step-faults were shown, and these have a downthrow on 
the west. (See p. 281.) 
The Rock-bed is well developed at Hoi well, Scalford, Eastwell, 
Eaton, Woolsthorpe, Cay thorpe, and Leadenham, where it furnishes 
a valuable iron-ore, and attains in places a thickness of 30 feet. 
The Marlstone, as a rock-bed, thins rapidly and entirely disappears 
at the north end of Welbourn ; moreover it does not set in again 
for a distance of some 12 or 13 miles to the northward. f 
* De Kance, Rep. Brit. Assoc. for 1879, p. 161. 
| Jukes-Hro ?vne, Geoli S.W. Lincolnshire, p. 33. 
