INFERIOR OOLITE : PONTON. 
209 
Lincolnshire 
Limestone 
(upper beds). 
Lincolnshire 
Limestone 
(lower beds). 
Great Ponton Cutting. 
Bubbly and shelly oolites, with nu- 
merous fossils .- Terebratula maxillata, 
Lima, &c. - ... 
Soft marl, with Ostrea - - 4 to 
Marly limestone, with Corals, Nerincea, 
and Turbo : irregular 
Coarse shelly oolites and freestones 
Little Ponton Cutting. 
Kubbly oolite, rag, and compact shelly 
beds, thick-bedded, some pisolitic 
about 
Clay - - - -0 2 to 
Compact marly and shelly rock, with 
Lucina, Pinna, Ostrea, Avicula, 
Trichites, Corals ... 
J Marly and oolitic limestones ; Gervillia 
acuta ----- 
Grey sandy clay - 
Marly oolite, with Pecten 
Compact marly and sandy rock, with 
Gervillia aciita, and Trigonia Phillipsi 
Ferruginous sandy oolite, with frag- 
ments of shells ; resting on sandy 
beds - about 
FT. IN. 
20 
1 
2 
15 
25 

12 
1 

30 
It is difficult to decide how far the above may represent a 
continuous section, whether there be a break in the series or a 
duplication. I am disposed to lake the latter view. The railway- 
cuttings are isolated and the beds are variable ; and between the 
two main' cuttings there are two shallow sections consisting of 
shelly pisolite with Ccrithium, Nerincea, and other univalves. At 
one point, as mentioned by Morris, the oolite rocks were pierced 
to a depth of about 60 feet in a well sunk close to the line of 
railway. 
East of the Witham river, between Great and Little Pouton, 
the Northampton Sand (brown ferruginous sandstone) was 
exposed in ditch-sections. Ironstone was shown for some distance 
along a narrow valley north of Ponton Park Woods, although 
not so represented on the Geological Survey Map. 
In the railway-cuttings there is little to be seen that was not 
recorded by Morris. The uppermost beds of Great Ponton show 
irregular dark and pale bands, the former being mainly oolite and 
the latter shelly limestone : the beds are more or less false-bedded. 
They rest on massive and rather marly oolitic freestone that is 
quarried to a depth of 10 feet by the railway. The more shelly 
beds are quarried by the lime-kiln south of Great Ponton railway - 
station ; and the freestones have again been extensively quarried 
at Houghton for building-stone and lime-burning. 
Most of the fossils obtained by Morris, were taken from the 
" Upper Shelly Beds at Ponton," and the rock (( whence the majority 
of specimens were obtained was a soft pisolite, the shells being 
generally well preserved and rarely broken. Associated with 
them were rolled fragments of marly rock and casts of shells in a 
similar matrix (chiefly Nerincea and Cerithmm\ much rolled and 
E 75928. 
