370 
Mr. Lyell 07 i the Boulder Formation^ 
terized by broken crag shells, and in one place some flint 
pebbles, occupying the space of several layers of loam. 
Fig. 17. 
clay and 
loam, 
loose sand. 
Section 8 feet high of vertical and curved drift in the cliff near Runton. 
Between the Runtons and Sherringham, and at a short 
distance from the latter place, are seen strata of vertical drift, 
on the one side of which are horizontal, and on the other 
curved and folded beds. The change in these cases from 
the horizontal set to the vertical is very abrupt. 
Crag near Weyhourne. — It is not until we arrive within less 
than two miles of Weybourne, that the Norwich crag appears 
in considerable force in situ above the level of the sea, in a 
cliff about 30 feet high, between Old Hythe Gap and Wey- 
bourne. At two different points I observed the chalk in con- 
tact with several feet of shelly sand and clay containing peb- 
bles and the fossils of the Norwich crag without any inter- 
vening breccia or ‘‘pan.” This crag was covered with clay 
and loam without shells. 
About half a mile from Cliffend, Weybourne, the following 
section appeared, in a vertical cliff about 40 feet high, where 
I saw the greatest thickness of crag abounding in shells : 
1st, horizontal chalk with flints, 8 feet; 2ndly, sand and flint 
pebbles with crag shells, 1 foot ; Srdly, fine sand with perfect 
crag shells, 10 feet; 4thly, sand and pebbles without shells, 
3 feet; 5thly, unstratified clay or till with flints, 10 feet. 
The following is a list of the shells obtained from this crag: 
Fusus striatus^ Littorina littorea, L, squalida (var. of prece- 
ding?), Purpura crispata^ perhaps var. of P. lapillus^ Cyprina 
islandica^ Cardium edule^ Cardium echinatum ? Tellina ohliqua, 
T. solidida, Nucula Cobholdicc, My a arenaria P Mactra, Astarte, 
