85 



these two species existed in the collections in the Territory. 

 The finding of more specimens of I. osborni (Muir) shows that 

 the aedeagns of the single specimen from wdiich the species 

 was described was damaged. The cyatliodes group shows some 

 interesting features for here we have certain chrootic changes, 

 which in other groups of Delphacidae are of generic value, 

 while the genitalia remain practically unchanged. 



All the new species show as great a phallic differentiation 

 as the old. In this question of phallic differentiation lies the 

 chief problem of the evolution of the Delphacidae, especially 

 of the evolution of species. Work done by Mr. Giffard on 

 North American Delphacidae shows the same diversity of the 

 genitalia as I have found among the Haw^aiian and Oriental 

 species. 



Mr. Timberlake made dissections and mounts of his own 

 material and that of Mr. Bridwell, and Mr. Giffard prepared 

 mounts and drawings of the material collected by himself, 

 and Messrs. Fullaw^ay and Eock, so that to a large extent T 

 am only the recorder of these new species. 



The types are all deposited in the collection of the Hawaii- 

 an Sugar Planters' Association, Honolulu. Measurements 

 are from the apex of vertex to the anus and from the base to 

 apex of one tegmen. 



The generic name Ilhurnia has been used in place of the 

 better known Nesosydne, but the change is unavoidable. 



Kelisia Fieb. 



Kelisia eragrosticola, n. sp. PI. IV, f. 2. 



Male. Brachypterous ; length 2.6 mm. ; tegmen i mm. Vertex slightly 

 longer than the width at base, apex slightly conically produced, narrower 

 than base, sides straight, converging towards apex, the Y carina obscure, 

 the diamond-shape cell not reaching the apex; length of face about twice 

 the width, widest about the middle, median carina simple; antennae 

 reaching about the middle of clypeus, first joint half the length of the 

 second. Pronotum about as long as vertex, lateral carinae straight and 

 slightly diverging to near hind margin, then slightly converging and 

 reaching the hind margin. Tegmina not reaching to the middle of abdo- 

 men. Hind tibiae longer than tarsi, first tarsus subequal to the other 



