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state of excavation, because it has been more thorongbly ex- 
plored than the remainder. It has also received great atten- 
tion in the careful registration of the bones, and the discrimi- 
nation of those of different beds. Moreover, no account of it 
has been given as yet (save in the British Association Report 
for 1875). In the spring of 1871 I described to the Cave 
Committee the beds inside the cave below the Roman-Celtic, 
and Neolithic layers, as consisting of — 
The Upper Cave-Earth, 
The Laminated Clay, 
The Lower Cave-Earth, 
and this distinction still holds good, although the Upper and 
Lower Cave-Earth ran together in one portion. Still the 
great thickness of laminated clay demands a corresponding 
length of time for its formation, and its absence or thinness 
at one point or another does not invalidate its existence 
elsewhere. Moreover, as will be seen, its importance as 
separating two distinct life eras in which different climatal 
conditions obtained cannot justifiably be overlooked. In 
their physical aspect the Upper and Lower Cave-Earth have 
much in common. The}' both consist of large and small 
angular blocks of limestone, intermingled with a stiff buff 
clay, occasional beds of stalagmite, and fallen blocks of sta- 
lactite. The limestone and stalactite have undoubtedly fallen 
from the roof. The stalagmite has formed upon the floor 
from time to time, when circumstances have been favourable. 
In the Upper Bed much of the clay seems to be derived from 
the laminated clay beneath, worked up and redeposited by 
water, or puddled by the animals whose bones are found 
in it; certainly where bones have occurred in the surface 
of this clay, it has lost its characteristic finely-bedded 
structure, and is simply homogeneous. A good deal of 
this homogeneous clay has probably been washed down 
through fine crevices in the roof by little runnels during wet 
