— 26— 



Antennse somewhat shortened, first joint short 3. 



Antennfe very long, first joint elongated. 

 Scutellum with 5 keels. 



Anterior tibiae longer than the femora and trochanters united. 



Interior ulnar and radial veins of corium of equal length, forked at base 



G. 6. Hygyops, A. et S. 



Interior ulnar vein shorter than the radial, the latter forked at base 



G. 7. Canyra, Stal. 



Anterior tibi;e as long as the femora G. 8, Livatis, Stal. 



3 Head broader than thorax G. 9. Amblycotis, Still. 



Head narrower than thorax or of ecjual breadth. 



Elytra convex. . G. 10. Rhinotettix, Still. 



Elytra flat or somewhat flattened. 



Posterior tarsi shorter than their tibipe 8. 



Posterior tarsi" as long as their tibire. 



Side keels of pronotum oblique, shortened behind 4. 



Side keels of pronotum attaining the postei ior margin, divergent ; frons with 



a median keel. 



Vertex a long isosceles triangle, without grooves or fovea?, with a median 



keel extending Irom one extremity to the other, ]-)iolonged lu-yoiid the 



eyes nearly half their length ; clypeus with a median keel ; basal an- 



tennal joint about one-third the length of second, thick, cylindrical; 



posterior tibire with two spines G, 11. Tropidocephala, Still. 



Vertex elongated, quadrangular, more or less prolonged before the eyes ; 

 frons with a median keel biforked on the vertex ; clypeus with a sharp 

 median keel ; basal antennal joint cylindrical, somewhat comjiressed, 



two-thirds the length of second which is cylindrical 



G. 12. Megamelus, Fieber. 



4 Frons M'ith two distinct keels, or else feeble above or nearly effaced, or more or 



less longly peduncled toward clypeus 6. 



Frons with one distinct median keel, entire or shortened, often scarcely, visible. 

 Frons with the apex of vertex forming an obtuse angle ; vertex pentagonal, 

 short, as long as wide at the base ; pronotum short, half as long as wide at 

 the base, pronotum short, half as long as the vertex with a median keel ; 

 side keels robust when with short elytra, feeble when with elytra \\ oil de- 

 veloped t^i- ij- Delphacinus, Fieber. 



Frons at apex and vertex at apex, truncated ; vertex quadrate or elongated 

 nearly trapezoidal. 

 Vertex a short isosceles triangle, or transversely quadrangular slightly passing 



the eye 5- 



Vertex quadrangular, elongated or trapezoidal, twice as long as wide, passing 

 nearly half or more than half its length before the eyes ; first posterior 

 tarsal joint much longer than 2 and 3 united, joints i and 2 deeply ex- 

 cised at the apex, their lobes straight. 

 Vertex elongated, trapezoidal, visibly wider at the nape of the neck than at 

 the apex ; frons elongated nearly hexagonal, widest about the middle 

 or at the apical third G. 14. Chlorion, Fieber. 



5 Frons with keel entire or forked only at the apex 



G. 15. Delphax, Fabr. (= Liburnia, Stiil.) 



