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fossil oysters found near Reading, in Berkshire, being about four 
inches and a half in length, and about two and a half in width. 
Dr. James Brewer, in the Philosophical Transactions for the year 
1^00, relates the following particulars respecting the bed of oyster- 
shells found under ground, near Reading, inBerkshire : — “The circum- 
ference where these oister-shells have been digged up and found, con- 
tains between five and six acres of ground. The foundation of these 
oister-shells is a hard rocky chalk, and above this chalk the oister-shells 
lie in a bed of green sand, upon a level, through the whole circumfe- 
rence, as nigh as can possibly be judged; this stratum of green sand and 
oister-shells is (as I measured) nigh two foot deep. Now immediately 
above this layre or stratum of green sand and shells, is a bed of a bluish 
sort of clay, very hard, brittle, and rugged : they call it a pinny clay, 
and is of no use. This bed or layre of clay, I found to be nigh a yard 
deep ; and, immediately above it, is a stratum of fuller’s earth, which is 
nigh two foot and a half deep — (this earth is often made use of by our 
clothiers) — and above this earth is a bed or layre, of a clear fine white 
sand, without the least mixture of any earth, clay, &c. which is nigh 
seven foot deep : then immediately above this is a stiff red clay (which 
is the uppermost stratum), of which we make our tiles. The depth of 
this can’t be conveniently taken ; it being so high a hill, on the top of 
which hath been and is dug a little common earth about two foot 
deep, and immediately under appears this red clay.” The doctor 
dug out several whole oysters, with both their valves, but found them 
very brittle. 
I have only to observe on these oysters, that they appear to be a 
variety of 0. edulis ; and that, from their long continuance in a sub- 
terranean situation, without any lapidifying impregnation, they have 
become so extremely friable, as to render it very difficult to obtain 
or preserve a good specimen. 
I have found, among the Essex fossils, besides one very much re- 
sembling the Bexley oyster, three other species. The one Plate XIV. 
