576 Mr. R. C. L. Perkins — Introduction to 



is not the case with the other class. Who can fail to believe 

 that a Looeops or a Hemignathus would have prospered on 

 Molokai had they ever reached that island? Although 

 Hmiatione ranges unchanged over six islands, yet after, by 

 some remote chance, reaching the very distant Laysan it has 

 there developed into a distinct form ; and the case of the 

 two extreme forms of Chlorodrepcmis on the rather distant 

 island of Kauai is also greatly in favour of my hypothesis. 



That any of the Drepanine birds cross even the narrowest 

 channels between the islands ivillingly is not to be thought 

 of. In times of storm they are often blown down to the 

 lowlands, sometimes in considerable numbers, in which case 

 they mostly fail to regain the forest and perish after a few 

 days. The only birds that I have myself picked up dead 

 (sometimes in numbers) on the coast after these storms are 

 of the genera Vestiaria, Himatione, and Psittacirosti-a; in 

 fact, the very forms which by their habits are most liable 

 to be carried away by the wind. Further, it is well known 

 that, after stormy weather, the two former sometimes reach 

 the bare island of Niihau, across the considerable channel 

 which separates it from Kauai, but they cannot live there 

 lonsr on account of its unsuitable nature. No doubt the 

 majority of these unwilling emigrants perish, but it is certain 

 that those blown from a high elevation on one island must 

 not infrequently land in suitable forest-country on one of 

 the others. 



10. Richness of the Island of Hawaii in peculiar Forms. 



The relative richness in birds of Hawaii, with its eleven 

 peculiar species and no less than six ]>eculiar genera, is 

 manifest and interesting, since in other groups of animals 

 with highly peculiar species it is frequently (though not 

 invariably) extremely poor, as compared with the older 

 islands of the group. Probably its large area and very 

 varying climate has favoured the multiplication of peculiar 

 forms, while it must not be forgotten that, owing to its 

 position at the end of the group of islands, it is incapable of 

 sending forth emigrants except in one direction. That this 



