INTRODUCTION cxci 



The Nabid genus Reduviolus and the Geocorid genus Nysius contain no less than 



50 of the 1 10 endemic Heteroptera, and both of these genera are cosmopolitan or 

 nearly so. The average number of species to a genus in the endemic Heteroptera 

 is only 3 '4, the many genera of Capsidae and Anthocoridae with few species, being 

 effectiv-e in the reduction. 



If we analyze the Homopterous constituents of the Fauna and exclude the 

 following species, introduced by man, viz. Peregrmus maidis and Perkinsiella 

 saccharicida (Delphacidae), Siphanta acziia (Poecillopteridae), Centroiypus sp. ? (Mem- 

 bracidae) and Phiynomorphus hospes (Tettigoniidae), there remain 16 genera with 

 128 species. 



The Delphacidae contain seven endemic genera, which are evidently allied to one 

 another, with 46 species in all, and one genus (not endemic) Kelisia, of independent 

 origin, with only three described Hawaiian species. The Tettigoniidae have four 

 genera represented, one of these, Nesophrosyne, and its offshoot, Nesophryne, containing 



5 1 described species, while Nesosteles contains four species, one of which is certainly, 

 and one probably, foreign. The Fulgoridae have two genera represented, one lolania 

 with a single variable species, the other Oliaj'us (cosmopolitan or nearly so) with 24. 

 The Psyllidae have two genera with four described species, all endemic. Subtracting 

 the two probably introduced Nesosteles, we have 126 Homoptera distributed in 16 

 genera and four families, an average of nearly eight species to the genus. Twelve 

 of the 16 genera are endemic. 



The contrast between the Homoptera and Heteroptera is therefore very great, and 

 one might say that the former, having a much smaller stock of ancient immigrants to 

 start with, has been far more successful in species-formation than the latter. Even 

 making all allowance for corrections and for additions to the fauna, this fact will 

 certainly remain true. 



CiMiciDAE. — The Cimicidae are very poorly represented by the one genus Oechalia, 

 of which the Hawaiian species are considered to be sub-generically distinct from the 

 typical Australian form. The number of species existing in the islands cannot be 

 considered as definitely settled at present. Two only are readily distinguishable, but 

 others will probably prove to be distinct. O. grisea, as now considered, presents 

 extreme variation in colour and structure, and of these varied forms it is likely that 

 some are in reality good species, and may themselves prove to be less variable 

 than grisea, as appears to be the case with the second species, O. kaonohi, lately 

 described. At any rate the nymphs present noticeable differences, and, so far as my 

 limited experience goes, similar nymphs have not produced adults varying in any very 

 important manner. Oechalia grisea is one of the commonest Hawaiian bugs, and 

 occurs even on the hottest and driest coasts, when the vegetation is green, and above 

 the upper limits of the forest on the high mountains. It is, however, most abundant 



