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by Teredines had long been known in a fossil state ; 
but the genus Pholas was unknown, except in Crag, 
until Mr, Goodhall was so fortunate as to pick up the 
specimen here figured, behind Lord Darnley’s park. It 
is a siliceous mass, from the uppermost stratum of Lime- 
stone near Sandgate. Exposure to the weather has laid 
open the shells to view in their natural situations in 
the fossil wood, part of which, being impregnated with 
silex, is preserved around the stony matter that has 
filled their cells. The mass also contains numerous 
single valves of a small Avicula. 
