FOSSIL SHELLS. 197 
inference, that the lower marine formation of our 
own country belongs to the same deposit; an infer- 
ence which derives additional strength from the 
well known similarity in the minerals of each. 
Beds of oysters-shells are found at Reading, 
nearly two feet thick ; at Donnington, in Berkshire, 
and about Winchester, where they are occasionally 
interspersed with sharks’ teeth. In the neighbour- 
hood of Broughton, in Lincolnshire, fresh-water 
shells, consisting of Pectinide FEcinites, and with 
pieces of coral, are often discovered, in quarries of 
blue stone. Kent has also its beds of shells; and 
twenty-eight different fossil species diversify the 
sands at Harwich. 
The digging of a moorish pasture in Northampton- 
shire, produced abundance of snail, and river shells, 
of various kinds. This place had no doubt been 
formerly overflowed with water, and its deposits had 
accumulated in the course of years to a bed of con- 
siderable thickness. Reculver, in Kent, is cele- 
brated for its alluvial deposition of white Conchites : 
these are at least twelve feet in thickness; they are 
imbedded in green sand, and occasionally varied with 
a few scattered pieces of wood. T'rochite, or St. Cuth- 
bert’s beads, as they are termed by the country- 
people, occur in the fissures of the rocks at Brough- 
ton and Stock, small villages of Craven. They are 
