In deep trenching in the Fen between Littleport and Shippea Hill in
order to obtain clay for laying on the peaty surface a very fine
unctuous deposit was found at a depth of four or five feet. The
overlying Fen Beds were chiefly peat with lenticular beds of white marl
and grey clay, obviously laid down from time to time in small
depressions in the surface of the peat. This marl was often largely
made up of, or was at any rate full of, freshwater shells but sometimes
showed evidence of having been gathered on the stems of Chara which on
perishing have left small cylindrical hollows penetrating the partly
consolidated marl. Under these beds of peat and marl there was the
unctuous clay, which is sometimes referred to as the Buttery Clay. It
is an estuarine deposit like that mentioned above as occurring in the
Wash off Heacham, for instance. It contains shells of _Cardium edule_,
_Tellina_ (_Tacoma_) _balthica_, _Scrobicularia piperata_, and other
estuarine shells, some of which had the valves adherent or rather
adjoining, for the ligament had perished. Mrs Luddington has in her
collection the bones of the Urus, Wild Boar and Beaver, obtained from
the peat above this Buttery Clay.
On the other or south-western side of Shippea Hill, which is an island
of Kimmeridge Clay, we get further into the embayed and isolated
portions of the Fen and we find more peat in proportion to the other
deposits although it is very thin. There are still small lenticular
beds of white marl similar to that nearer Littleport and the peat rests
upon Buttery Clay of unknown thickness. In this part, however, no
shells have yet been noticed. Near Shippea Hill the peat has recently
been trenched with a view to obtaining clay with which to dress the
surface of the peat and it was here, at a depth of four feet from the
surface and four inches above the Buttery Clay, that the human bones
described below (pp. 27-35) were found.