INTRODUCTION xlvii 



timber can be seen from the study of the little weevil, Diyotribns 7ninieticus, whose 

 natural home appears to be in drift-wood, and which not only occurs in Florida, but in 

 the Hawaiian group and in Australia. In the case of the Hawaiian fauna many of the 

 winged insects might quite possibly have been transported in this manner, for in their 

 larval stages they live in the wood of dead trees, or beneath or in the bark, or they 

 frequently, even if leaf-eaters as larvae, creep into the cavities of dead branches or 

 beneath the bark to pupate. It is only necessary to look through the various families 

 of insects, the habits of which are recorded hereafter, to see what a great proportion 

 might have been carried in this manner. As is well known the common drift of the 

 islands, derived from outside, consists of coniferous trees from North-West America, 

 but few and probably none of the elements of our fauna can have been derived thence. 

 Our insects have no relationship with those from that quarter, and it is unlikely that 

 such drift would bring insects that would become acclimatized in the islands. Roughly 

 speaking the Hawaiian fauna may be said to have been derived, so far as we can judge 

 from its affinities, from immigrants received from the warmer parts of America, from 

 the Australian and South Polynesian islands, and from the Oriental region. I do not 

 place much importance on the fact that there is certainly no regular deposit of drift 

 wood from any of these regions at present on the island shores, for with our scanty 

 representation of types, it is only necessary that once in thousands of years an immi- 

 grant-bearing trunk or log should reach them. Certainly a careful consideration of the 

 components of the Fauna would lead us to believe that this must have happened. 

 Dr Guppy places little importance on drift in his considerations of the origin of the 

 Hawaiian flora and very great importance on the birds ; but when I consider how often 

 1 have found great numbers of seeds held beneath the dead bark of trees in the 

 mountain forests, I cannot overlook the possibility of original components of the flora 

 having arrived this way, as have those of the fauna. Further when one considers that 

 even in our limited fauna, a single tree trunk may contain a score or more of distinct 

 species, beetles and their larvae in the wood and bark, caterpillars boring the wood or 

 living beneath the bark, well-sealed nests of bees and wasps, often in old beetle 

 borings, with possibly Mollusca adherent to the bark, or beneath it, or wedged in 

 crevices, besides other creatures and perhaps parasites of some of these, we may fairly 

 suppose that once in a long period, some such micro-fauna may have been washed out 

 to sea and stranded on these islands, and that some at least of the emigrants have 

 survived and become established. 



Though the distance between the islands and other lands is so great, yet we know- 

 that, like the migrant birds of Alaska that regularly visit the islands, certain insects 

 of migratory habits like the large dragonflies, the butterflies, Pyrameis cardui and 

 Imntcra, the small moth, NoniopJiila noctttclla, and others have been able to reach 

 the islands, and probably still do arrive from time to time, so we need not feel any 

 difficulty in believing that at some j^eriod a lesser-sized dragonfly (Agrion) or an 



