various species of snoar-cane leaf-hoppers. Another Tet- 

 rastichine, Neotetrasticlius mimus T cannot fit into any hitherto 

 described genns. It is superficially extremely similar to some of 

 the species of Ootetrasticlius, but it has very different antennae. 



Ootetrastichus. 



Ootetrastichus Perkins, Bull. Exp. Station Hawaii, I, 263. 



This genus was founded for the single species O. heatiis Perk., 

 of which only the female was known. It is remarkable in this 

 sex for the 7-jointed antennae, which possess in addition appar- 

 ently three ring-joints, or even sometimes have the appearance 

 of bearing four such joints. 



Although O. heatus has now been under observation for seven 

 or eight years and has been bred generation after generation 

 for long periods of time, no male has ever been seen, either in 

 these islands, where it is fully established and now very common, 

 or elsewhere. 



On the other hand the males of four other species, described 

 below are now known. In general structure they are like the 

 females, but even in life their sex would be easily recognized 

 by the enormously dilated scape of the antennae. These organs 

 are unlike those of the female, having two additional joints, 

 the complex nature of the ring joints being the same in each 

 sex. The scape of the male is ovate, long and large; there are 

 four elongate funicle joints, not usually differing very much 

 in length, and a distinctly three-jointed club. In one species 

 (0. liolocMorus) the uuirginal vein is notably thickened and in 

 some males there is a sexual modification of the apical joint 

 of the front tarsi. 



SYNOPSIS OF SPECIES 



1. Antennae with 9 joints in addition to ring-joints (males) 



; 10 



Antennae with 7 joints in addition to ring-joints (fe- 

 males) 2 



2. Hind coxae pale, not metallic 3 



Hind coxae. dark, metallic 5 



3. Mesonotum with conspicuous dark area in front, this 



area metallic in dry examples 0. heatus 



Mesonotum without metallic dark area in front. 



