166 EXPLANATIONS. 



much apart, its plants and animals are never found 

 allied to those of any remote region of the earth, 

 but invariably show an affinity to those of the 

 nearest larger masses of land. Thus, for example, 

 the Galapagos exhibit general characters in com- 

 mon with South America; the Cape de Verd 

 islands, with Africa. They are, in Mr. Darwin's 

 happy phrase, satellites to those continents in 

 respect of natural history. Again, when masses 

 of land are only divided from each other by 

 narrow seas, there is usually a community of 

 forms. The European and African shores of the 

 Mediterranean present an example. Our own 

 islands afford another, of far higher value. It 

 appears that the flora of Ireland and Great 

 Britain is various, or rather, that we have five 

 floras, or distinct sets of plants, and that each of 

 these is partaken of by a portion of the opposite 

 continent. There are, 1st, a flora confined to the 

 west of Ireland, and imparted likewise to the 

 north-west of Spain ; 2nd, a flora in the south- 

 west promontory of England, and of Ireland, ex- 

 tending across the Channel to the north-west coast 

 of France ; 3rd, one common to the south-east of 

 England, and north of France ; 4th, an Alpine 

 flora developed in the Scottish and Welsh High- 



