38 Origin of the British Flora. 
view of a naturalist, the comparative importance of the 
different stages and of the different agencies, and even the 
reading of the physical geography, will assume an aspect 
very unlike that ordinarily laid before the student. To 
the extreme glacialist the ‘ Pleistocene’ is equivalent to the 
‘Glacial’ Period, and the scattered relics of Interglacial 
mild epochs are judged to be of small importance. It may 
be thought that the following notes go to the opposite 
extreme. I believe, however, that the accumulation of ice 
and snow merely marked two or more culminating epochs 
in a period when the climate was at least as commonly 
temperate as Arctic. The geological evidence for this I 
have already published (see also below ‘Hoxne, p. 77; 
‘Selsey,’ p. 88; ‘West Wittering,’ p. 94.) 
The appearance of man in this country is sometimes 
thought to mark a new era; but, as far as our present 
information goes, it was long before he had much influence 
on the character of the fauna and flora. Paleolithic man 
was only one more carnivorous animal added to a fauna 
which already possessed several quite as dangerous, and 
apparently occurring in greater numbers. He did not 
cultivate the ground, and therefore would not introduce 
weeds of cultivation. Wedo not know whether he often 
crossed the narrow seas ; though it is doubtful whether an 
occasional canoe, not freighted with vegetable produce, 
would greatly aid in the dispersal of plants which could be 
carried by so many other messengers. It was not till 
Neolithic man appeared, with domesticated animals, culti- 
vated plants, and probably with more seaworthy canoes, 
that the human race took a leading part in the dispersal 
of seeds. It still remains to be seen how large a proportion 
of our plants were unrepresented in Britain before his 
days. 
We have now to trace in a few words the succession of 
