THE MIDDLE LIAS OF NORTHAMPTONSHIRE. 
41 
And the Clay-beds below contain about the same fossils, but 
the material is so soft that they are difficult to get out whole. 
I think beds 3, 4, 5, and 6 must be regarded as belonging 
to the “ Spina tits ” Zone , and 7 and 8 to the “ Margaritatus ,” 
using the brachiopods as indicators. This course of using the 
brachiopods seems to be the best in Northamptonshire, where 
the characteristic ammonite of the “ Spinatus ” Zone is 
almost entirely absent, and A. margaritatus not very 
abundant nor having well-defined vertical limits. 
On comparing the section given above with Prof. Judd’s 
“ Geology of Rutland,” page 76, I think I must conclude 
that the laminated ferruginous sandstone, which he thought 
represented the Rock-bed, is worked out; there seemed to be 
nothing like it on the occasion of my visit. In other respects 
the section seems to have changed considerably. 
We have so far been considering sections situated near the 
westerly limits of the Middle Lias outcrop ; there are several 
others within the Middle Lias area that are worth noticing, 
and first let us take the one at Badby. This section I have 
found rather puzzling, for under undoubted Upper Lias, and 
where I expected to find the Rock-bed, was a bed containing 
a number of Rock-bed fossils, together with others that I had 
usually looked upon as characteristic of lower beds, so that 
the following arrangement is given provisionally. 
Section, East of Badby. 
1. —Soil, passing into a light-coloured marly clay con¬ 
taining many little ammonites. Communis- 
beds ... .. ... ... ... ... 2 to 3 
2. —Cephalopoda Bed, fragmentary, nodular, contain¬ 
ing :— Ammonites communis , <fc., Belemnites, 
Lucina Bellona, Aviculce , Serpulw , Pentacrinite 
joints. 
3. —Transition-bed. In one spot, between the Cepha- 
lopoda-bed and Rock-bed, there is a thin patch 
of soft stone, containing an immense number 
of dwarfed gasteropoda and other fossils—at 
least twenty species of fossils were obtained— 
and this I have very little doubt represents the 
Transition-bed. 
4. —Rock-bed, a thin layer of higlily-fossiliferous stone 
capping, and passing without any break into 
the next bed, containing: — Pecten liasinus 
(rather large and abundant), Ostrea cymbium , 
Plicatula sp.? Terebratala punctata, Terebratula 
Edwardsi, Rhynckonella tetrahedra , Rhynchonella 
fodinalis. 
