INTRODUCTION ccv 



Consequently the separation of the numerous species is attended with considerable 

 difficulty, very few apparently being notably distinct from their nearest congeners. 



Some of the smallest and most obscure forms are strictly attached (e.g. O. kaonohi) 

 to tree ferns, in the cavities of the stems of which, especially when they are fallen and 

 more or less decayed, the nymphs are found living gregariously. Most of the finer 

 species, however, are attached to various forest trees, and of some of these the nymphs 

 live beneath the bark, sometimes in large flocks, sometimes associated with the adults. 

 In such situations the amount of honeydew excreted, not being exposed to sun or wind, 

 accumulates in extraordinary amount. Apparently several of the species are entirely 

 restricted to one kind of tree (e.g. O. taniehanieha on Metrosideriis) but the observations 

 on this point are not conclusive, since they have not been made in sufficient numbers, 

 nor in sufficiently numerous localities. Of these more conspicuous arboreal forms the 

 apparent scarcity of many is, doubtless, more apparent than real, for we have observed 

 some of these in considerable numbers on the trunks or stouter branches of the smaller- 

 sized forest trees, on which they run with considerable quickness, and with the rapid 

 sidling movements of the larger Fulgorids of other countries. In such circumstances 

 they do not readily admit of capture, and if the branches be jarred, the majority of the 

 individuals no doubt escape, their strong jump combined with flight carrying them 

 beyond the limits of any receptacle held beneath. Though of universal occurrence, 

 where native insects are found, they will probably be found most richly represented in 

 wetter forests, with very heavy rainfall. One species at least, a small and prettily 

 marked one, lives on a liliaceous plant (As^e/ia), growing in abundance around the 

 volcano house at Kilauea on Hawaii. 



AsiRACiDAE. — Excluding two or three genera, the species of which are either 

 certainly introduced or possibly natural immigrants, the six endemic genera of Asiracid 

 (often known as Delphacid) leaf-hoppers form a remarkable assemblage of allied forms, 

 notable for the similarity of structure in the jumping spur of the tibiae. There is little 

 doubt, I think, that they have originated from the same ancestral immigrant, the generic 

 divisions of the present-day assemblage having" proceeded on lines quite similar to 

 those followed by other genera of Fulgoroids in other parts of the world. At the same 

 time the genera are very well marked indeed, as defined by Kirkaldy, though I antici- 

 pate that forms connecting some of these more closely, remain to be discovered. In 

 this connection it is interesting to note that in the mountains close to Honolulu there 

 occurs (at present undescribed) a form in which, though quite similar in general 

 characters to other Hawaiian species, the frontal keels remain separate and well defined 

 for half their length, in this respect being intermediate between Aloha and Nesorestias 

 on the one hand and the remaining endemic genera on the other. 



There appears to be no material difference in habits between the representatives 

 of the different genera, considered collectively. After spending considerable time in 



