48 



PAPEKS. 



On the Genus Ilburnia White (Homoptera, Delphacidae). 



BY F. :MriR. 

 (presented by w. m. giffard.) 



Uhurnia White 1878, Proc. Zool. Soc, Lond. p. 471. sub- 

 genus of Liburnia Stal. 



Nesosydne Kirkaldy 1907. Proc. Haw. Ent. Soc. I. p. 161. 



In the British Museum collection there are two female 

 specimens under the name of Ilburnia ignobilis White, col- 

 lected by Wollaston on Diana's Peak, St. Helena. The type 

 is in good condition but the second specimen, which is smaller 

 and darker and represents another species, is without tegmina. 

 The shape of the tibial spur places them among the Alohini 

 and there is no structural diiference to separate them from 

 Nesosydne Kirkaldy. Delpliax siniulans Walker, collected by 

 Darwin in the Galopagos Islands, also has to come into the 

 same genus although it is not quite typical. This makes the 

 present known geographical distiibution for this genus, Hawaii- 

 an Islands, with many species, Galopagos Islands, with one 

 species, and St. Helena, with two species. I. ignobilis. White 

 and 7. simidans (Walker) are redescribed below. 



Unfortunately the name Nesosydne,. so well known to our 

 local collectors, will have to give place to Ilburnia. 



Ilburnia ignobilis White. 



Head much narrower than thorax ; vertex slightly longer than width 

 of the base, apex narrower than base ; length of face a little more than 

 twice the width, slightly narrowed between the eyes, median carina sim- 

 ple ; clypeus tricarinate ; antennae long, reaching to apex of clypeus, 

 terete, joints subequal in length, second slightly thicker than the first. 

 Pronotum and mesonotum tricarinate, lateral carinae of pronotum diverg- 

 ing, straight, reaching hind margin. Tegmina not reaching to the middle 

 of abdomen, truncate at apex. Legs long, slender, first hind tarsus longer 

 than second and third together, spur nearly as long as first tarsus, nar- 



Proc. Haw. Ent. Soc, IV, No. i, June, 1919. 



