MIDDLE CHALK, LINCOLNSHIRE. 
481 
to 15 feet in thickness, and the following is the section visible in 
Mr. Clapham’s quarry by the London road south of Louth:— 
Terebra- [ White chalk in thick beds with layers of flints 
tulin.'< Similar chalk, some beds very hard 
Zone. .Hard white chalk, not much jointed 
Zone of 
Rhyne h. 
Cuvier i 
Layer of loose grey shale - 
Hard shelly chalk in beds from 12 to IS incl 
thick, separated by layers of grey shale 
Buff coloured sandy shale with nodules of 
hard chalk (Inoceramus mytiloides ) 
JJard greyish chalk, with shaly partings 
Grey and purple shaly marl (Belemnite Marl). 
ft. in. 
.30 0 
12 0 
0 6 
0 6 
8 0 
0 6 
4 0 
The same succession can be seen in Mr. PaddisoiTs quarry north 
of LiXith, and again in a quarrv at Elkington Pasture, about a mile 
W.N.W. of Louth. 
Near Caistor this zone is well shown in a quarry by the windmill 
south-east of the town, as below .— 
ft. in. 
Soil and chalk rubble. 3 0 
Hard white chalk with two layers of flints - - 6 0 
Zone of [Shale and shaley chalk - - 0 9 
Rh. (Hard greyish chalk in beds about a foot 
Cuvieri. [ thick, with partings of grey shale - - - 11 0 
Soft grey shale (seen at one place). 
The same beds are exposed in two pits near Both well, one half a 
mile south-east, and the other W.N.W. of the village ; the beds of 
greyish chalk are divided by layers of yellowish marly shale from 
4 to 6 inches thick, containing small loose nodules or lumps of chalk. 
From these localities I obtained Am. [Pachydiscus] peramplus 
(young), Inoceramus mytiloides, and Rhynckonella Cuvieri. 
The whole zone is well exposed in the large quarry north-east of 
South Ferriby, part of which section has been given on p. 222; the 
details of the upper part will be found on p. 484. 
Terebratulina Zone. 
This zone is found along the whole length of the Lincolnshire 
Wolds, but it is often cut through by the deep valleys which traverse 
the hills, and consequent^ it is divided and partitioned out into a 
number of irregular outliers and patches of various sizes. There 
are many exposures, all the most important of which have been 
noted in the memoirs of the Geological Survey already published,* 
so that we only need mention a few of the largest and best sections. 
* Geology of East Lincolnshire, by A. J. Jukes-Browne, 1887; Geology 
of the Country around Lincoln, by W. A. E. Ussher, A. J. Jukes-Browne 
and Aubrey Strahan, 1888; Geology of Parts of North Lincolnshire and 
South Yorkshire, by W. A. E. Ussher and others, 1890. 
