416 



INSULAE FLOKAS AND FAUNAS WITH 



[Ch. XLI. 



Atlantic islands, represented in each separate arcliipelago by 

 distinct species. 



Mr 



WoUaston 



Atlantidum/ has described no less than 1,449 species of beetles 

 belono-ing to the three gronps of islands above mentioned. 

 Nearly all of these have been collected by himself, and of the 

 whole nnniber more than 1,000 are of species hitherto unknown 

 as inhabiting any other region, although there is no donbt that 

 a great many of them will hereafter be discovered in lands 

 bordering the Mediterranean. The distinctness of the fauna 

 of different archipelagos is shown by the fact that out of 



rom the 

 common 



Even 



of these it is suspected that the larger number have been 



man 



modern times 



Nearly every detached island adds some distinct species or 

 marked variety to the general list, and one half of the 24 

 species foimd on the rocks called the Salvages, before men- 

 tioned, are peculiar, some of them belongiu^ 

 which have been called Atlantic types. ' If,' says WoUaston, 

 ^ we exclude those beetles which have probably been natura- 



human ao^ency, there are marvellously 



permeate 



common 



Among the 



dominant forms 



of them are of essentially 



greatly, and certain families 

 Atlantic types. No less than 50 species and varieties feed 

 exclusively on the Euphorbias which are so abundant and 



in the Canaries. Some fossil plants of 



form 



Miocene strata of (Enin 



in Europe, and the parent stock both of these plants and of 

 the Atlantic CurculionidcB may perhaps have been derived from 



continent. It has been already proved, by the 



Miocene 



researches of Heer and others, that the Miocene Coleopterous 

 Eauna of Central Europe was actually richer than that now 

 living in the same latitudes ; ^ so that we may well imagme 

 that the various means of transport already alluded to (p- 379), 



^ See 'Lyell's Elements of Geology/ p. 254, 



