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. y/ ; 

 ' 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. Palaeolithic 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. We do 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 



