54 
^Thomas Walford, Esq. has nearly similar remains of 
shells on his estate at Birdbrook, N. W. of Castle Hed- 
ingham, Essex, of which he kindly sent me a specimen, 
in the light chalky marl, perhaps alluvial on the London 
clay ; but I expect, from what I have, that the siphunele 
is placed about one-third of the length of the mouth from 
the last whorl ; and although the flatness and width of the 
shell nearly corresponds, it is not so angular as in the 
Keynsham specimen. It was part of a septarium, which 
included the shell, indiscriminately, as a mass of earth. 
Such light earthy septaria are found under gravel, near 
the Marquis of Cornwallis’s, Culford Hall, near Bury 
St. Edmund’s^ Suffolk. 
