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during the Glacial period was such as to destroy 

 a large proportion of the vegetation. The question 

 is, Avere all the flowering plants destroyed or were 

 some of the hardier species able to survive, either on 

 the higher peaks which kept their heads above the 

 level of the ice or on the southern fringe of England 

 beyond the ice-covered region ? It is impossible to 

 give a definite answer : the probability is that nearly 

 all the pre- Glacial species were destroyed, but it is 

 not impossible that some Alpine-Arctic plants escaped 

 extinction, while others retreated to more southern 

 and less Arctic areas by means of a land-connexion 

 with France or crossed the intervening sea by ocean- 

 currents, by animal agency, or by wind. 



Although we possess but imperfect information as 

 to the extent and duration of land-bridges between 

 Britain and the continent, there are no special 

 difficulties in the way of accounting for the presence 

 of Scandinavian, Germanic, and other elements in the 

 British flora. There are, however, other and more 

 difficult problems to consider in reference to a small 

 group of flowering plants which are met with in the 

 west and south of Ireland, also, to a less extent, in 

 Cornwall and in a few other localities in the south- 

 west of England. In Connemara in the west of Ireland, 

 where hard frosts are unknown and winter snows are 

 rare, there are three kinds of Heath, St Dabeoc's Heath 

 (Dabeocia poli/olia), the Mediterranean Heath (Erica 



