The Origin of our British Flora 



always slightly changing. There are also, of course, 

 the usual weeds of worldwide distribution, such as 

 the common nettle, Luzula campestris, common avens, 

 bracken, and black maidenhair spleenwort. Of these 

 there are said to be no less than 182 species.^" 



But there are two other difficult questions which 

 ought perhaps to be mentioned. 



In Scandinavia an invasion of the beech followed 

 after and dispossessed the oak. In some German maps 

 the beech is shown as dominating practically the whole 

 of northern and middle England. That, however, does 

 not seem to have been proved, for no evidence can be 

 drawn from our modern woodlands, which are all more 

 or less artificial, and the ancient English forest seems 

 to have been oak or beech. Yet the tree is supposed to 

 be a native. Gerard, in 1597, says: '' Fagus ... in 

 many forrests and desart peaces ... in Kent." It is 

 particularly common now on chalk and limestone. 



Yet one can hardly believe that a beech forest in 

 prehistoric or early historic times ever entered England 

 and displaced the British oak. 



The steppes at one period in glacial times entered 

 Europe and extended certainly into France and Swit- 

 zerland. 



In the east of England there are several counties 

 which possess a far drier and sunnier climate than is 

 usual in Britain ; but, so far at least as the author is 

 aware, the characteristic steppe plants have either never 

 reached England at all, or failed to hold their own if they 

 did manage to enter during the first interglacial epoch. 



But there is a whole series of very interesting plants 

 which may really be relicts of that very distant time. 

 The best known of them are the arbutus, and the 

 Cornish and Mediterranean heaths. One might also 

 mention the wild asparagus, Simethis, Romulea, Poly- 



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