14 MY ISLANDS. 



mainland, and so they have produced at last a special 

 island type, exactly adapted to the peculiarities of their 

 new habitat. 



You see, there was hardly ever a big storm on land 

 that didn't bring at least one or two new birds of some 

 sort or other to the islands. Naturally, too, the new- 

 comers landed always on the first shore they could sight ; 

 and so at the present day the greatest number of species 

 is found on the two easternmost islands nearest the 

 mainland, which have forty kinds of land-birds, while 

 the central islands have but thirty-six, and the western 

 only twenty-nine. It would have been quite different, 

 of course, if the birds came mainly from America with 

 the trade winds and the Gulf Stream, as I at first antici- 

 pated. In that case, there would have been most kinds 

 in the westernmost islands, and fewest stragglers in the 

 far eastern. But your own naturalists have rightly 

 seen that the existing distribution necessarily implies 

 the opposite explanation. 



Birds, I early noticed, are always great carriers of 

 fruit-seeds, because they eat the berries, but don't digest 

 the hard little stones within. It was in that way, I 

 fancy, that the Portugal laurel first came to my islands, 

 because it has an edible fruit with a very hard seed ; 

 and the same reason must account for the presence of 

 the myrtle, with its small blue berry ; the laurustinus 

 with its currant-like fruit; the elder-tree, the canary 

 laurel, the local sweet-gale, and the peculiar juniper. 

 Before these shrubs were introduced thus unconsciously 

 by our feathered guests, there were no fruits on which 

 berry- eating birds could live ; but now they are the only 



