British Islands, Shetland, Feroe^ and Iceland^ 41 



Botanists had long remarked that certain islands possess 

 a flora which is peculiar to them, while others present no 

 plant which is not found on the nearest continent. Such is 

 the case with the British Islands ; but we shall not confine 

 ourselves to the study of the vegetation of England, Scotland, 

 and Ireland, but endeavour to follow the vegetable migra- 

 tions in that series of archipelagoes, islands, and islets, which, 

 under the name of Orkneys, Shetland, Feroe, and Iceland, 

 form the only chain which unites middle Europe to North 

 America. 



Let us first attend to the botanical geography of the British 

 Islands. In this study we have for our guides the beautiful 

 works of Mr Hewett Watson* and Mr Edward Forbes. t 

 Both have carefully examined their country ; the one as a 

 botanist, the other as a zoologist and geologist. An im- 

 portant and capital fact gives all the results to which these 

 naturalists have arrived, namely, that the British Islands do 

 not furnish a single plant which is not found on Continental 

 Europe. t These islands cannot, therefore, be considered as 

 a centre of vegetation, since all the plants which inhabit 

 them likewise exist on the European Continent. But all do 

 not come from the same regions of Europe, and we shall re- 

 cognise, along with Messrs Watson and Forbes, a series of 

 vegetable migrations which have successively colonised the 

 British Islands. 



1. Asturian Type, — Owing to the mildness of its winters, 

 Ireland has preserved for us, so to speak, the remains of a 

 peninsular flora. In the south-west of that island, we find 

 in a wild state, twelve plants, original natives of the Asturias, 

 which have maintained themselves in Ireland as the last 



* Remarks on the Geographical Distribution of British Plants, chiefly in 

 connection with Latitude, Elevation, and Climate. One vol. 8vo, 1835 ; and 

 Cybele Britannica, vol. i., 1847. 



t On the Connection between the Distribution of the Existing Fauna and 

 Flora of the British Isles, and the Geological Changes which have aflfected their 

 Area, especially during the epoch of the Northern Drift. {Memoirs of the Geo- 

 logical Survey of Oreat Britain, vol. i., p. 336, 1846.) 



J A single species only, Eriocaulon septangulare, cast on the shores of the 

 Hebrides, is a native of North America. 



