THE FAUNA OF BRITAIN. IOI 



origin of the British species. They represent merely 

 groups of assemblages of plants of different types 

 of vegetation. Edward Forbes, on the other hand, 

 founded his districts on the origin of plants. His 

 work is not only the first of the kind, but it is a 

 classical essay, and remains one of the most remark- 

 able contributions to the literature on the geographical 

 distribution of living organisms known to science. 

 The vegetation of the British Islands, he informs us 

 (p. 4), presents a union of five well-marked floras, 

 four of which are restricted to definite provinces, 

 whilst the fifth, besides exclusively claiming a great 

 part of the area, overspreads and commingles with 

 all the others. These are 



I. Mountainous districts of South-) T 



west and West of Ireland . . [Lusitaman type. 



II. South-west of England, and),- ,,. 



South-east of Ireland . , .) Galilean type. 



III. South-east of England. 



IV. Mountains of Scotland, Cumber-) c j- 



land, and Wales . . . .j Scandinavian type. 



V. General Flora Germanic type. 



Professor Forbes points out, in connection with the 

 plants of the Germanic type, that the fauna accom- 

 panying this flora presents the same peculiarities and 

 diminishes westward and to the north. This type 

 includes, therefore, almost all the species which can 

 be shown to have come to us directly from the east, 

 few if any of which have penetrated to Ireland. 



On a previous occasion, the same author had 



