EAST MIDLAND DISTRICT. 71 
its Kast Midland character, the section at Hook Norton, read by the light of Mr. 
Walford’s experience, is both interesting and instructive. Between the Upper Lias 
Clay and the Great Oolite are 31 feet of beds. These are divided into five groups. 
The lowest group, 4 feet 9 inches, is a sandy blue hearted limestone with corals. It has 
yielded Rhynchonella cynocephala and some few Gasteropoda characteristic of a low 
horizon. Since it is by no means easy to separate the Opalinus- from the Murchisone- 
zone, this group may be taken as representing the zone or zones usually charac- 
terised by those two Ammonites. The second group, 10 inches thick, contains an 
Ammonite-bed ; the species being one of those smooth, flattish forms, similar to 
the prevailing types in the concavus- or so-called Sowerbyi-beds of Bradford Abbas. 
Terebratula perovalis likewise is quoted from here. Both the first and second 
group belong to the Lower Division of the Inferior Oolite. Next comes the usual 
hiatus, and then the third yroup, 2 feet 10 inches, has a shell-bed towards the top 
with undoubted fossils of the Parkinsoni-zone; and in this shell-bed are several 
species of Gasteropopa. If this group represents the Trigonia-grit, the Gasteropoda 
he at the top, mstead of at the bottom as in the Aston cutting. The fourth and 
Jjifth groups of this section call for no notice here. They are bulky and for the 
most part devoid of Mollusca, and serve to show the changeable nature of the 
uppermost beds of the Inferior Oolite hereabouts. 
Derains or THE Hast Mipianp District (No. 3). 
The first fossiliferous beds of Inferior Oolite age in this district which attract 
our attention are those at Blisworth and round the town of Northampton (Duston, 
&c.), which were regarded by Mr. Sharp as in the zones of Am. opalinus and Am. 
Murchisone. I see no reason to doubt Mr. Sharp’s determination, the more so as 
there is a certain degree of resemblance between the Yorkshire Dogger and the 
Northampton Sand. Cephalopoda are not plentiful, but the Conchifera are large, 
especially Lima, and fairly numerous. The Gasteropoda are not particularly 
abundant, nor in a satisfactory condition for determination, occurring principally 
_ as impressions in the ironstone. Hence they are not very nice cabinet specimens. 
It is not probable, therefore, that many, if indeed any, of these specimens will be 
selected for figuring; but they will at all times be useful for correlation in those 
cases where the species can be made out with certainty. The best specimens are 
in the Sharp collection at the British Museum. At present I am informed by Mr. 
George and Mr. Beeby Thompson, that it is not easy to obtain many specimens of 
interest from these beds. 
But the main feature of Inferior Oolite age in the Hast Midland District is the 
Lincolnshire Limestone. The chief characteristics of this important series are 
