PalcolitJi and N eolith. — Claypolc. 343 
cept certain implements of palaeolithic type reported from below 
the great chalky boulder clay and remarks on "the archaeo- 
logical difficulty that man at two such remote epochs as the 
preglacial and the postglacial, even if the term glacial be 
limited to the Chalky Boulder clay, should have manufac- 
tured implements so identical in character that they cannot be 
'distinguished apart." 
Now waiving the question whether or not these imple- 
ments of palaeolithic age can be distinguished, this sentence is 
scarcely in accord with the following which occur later in 
the same address: 
The duration of the pa'.seolithic period must have extended over 
an almost incredible length of time, for valleys some miles in width 
and of a depth of from 100 to 150 feet have been eroded since the 
deposit of the earliest implement-bearing beds. 
Again we read: 
We have seen that during the migration of palaeolithic man from his 
original home to the west of Europe the forms of the weapons and 
tools made from siliceous stones had become stereotyped and that 
during the extended period implied by the erosion of the valleys the 
modifications in the form of the implements were but slight. 
If, then, so little modification occurred in the pattern of the 
implements during all the long palaeolithic time there can be 
no difficulty arising from the close resemblance of the speci- 
mens made before and after the deposition of the chalkv boul- 
der clay. 
All the difficulties, real and imaginary, that can be brought 
forward disappear, however, when we accept the conclusion 
of Prof. Geikie. Palaeolithic man in England w'as a member 
of the southern mammalian fauna, lived in Britain in the inter- 
glacial period perhaps even during the presence of the ice, 
disappeared with the fauna to which he belonged and his 
place was taken, after an interval, by neolithic man, a member 
of another fauna with different arts and methods and doubt- 
less coming from a dififerent region. 
We need not infer from what has been said that P)ritain was 
occupied by palaeolithic man during all the interglacial pe- 
riods though the evidence may some day prove this to have 
been the case. Still less can we infer the existence of ])re- 
glacial man in the same region, though this also awaits proof. 
