67 



Two apical wing cells | Ciroup Bj (**) (6) 



One apical wing cell [Group C] ('"*) (ii) 



Tegminal appendix present (5) 



Tegminal appendix absent, subniarginal wingvein present 



• ••••; •• •••• (10) 



Submarginal wingvein present i Alebra 



Submarginal wingvein absent 2 Protalehra 



Submarginal wing vein present ; third apical wingvein fork- 



ed (7) 



Submarginal wingvein absent (9) 



At least two of the apical cells of the tegmen arising from 



the transverse veins (8) 



Only one of the apical cells arising directly from the trans- 

 verse veins 5 Kahaono 



Body long and slender 3 Dikraneura 



Body short and robust ' 4 Erythria 



First two wing veins subparallel 6 Eupteryx 



First two wing veins confluent towards the apex 



7 Erythronciira {=:.Enipoa) 



\'ertex twice as long as pronotum 8 Nirvana 



\'ertex shorter than pronotum 9 Eualcbra 



Submarginal wing vein present. 10 Cicaditla (=Enipoasca) 



Submarginal wing vein absent 11 TyphlocyhcUa 



A^rtex wider than an eye. not produced anteriorly, form- 

 ing a curve with the eyes ; frons not twice as long as 



maximum width 12 AphcUona 



(type Hcliona hiocula Melichar) 

 12a A^rtex narrower basally than an eye, angularly produced 

 anteriorly ; frons elognate, mofe than 3 times as long as 



maximum width ; lora elongate 13 Hehona 



13 A^ertex not produced in front of eyes; radial and median 



with a common apical stalk 14 Dialecticopteryx 



13a A'ertex triangularly produced; cubital and median with a 

 common apical stalk 15 Aneono 



It appears to me that a form with three apical wing cells and 

 a tegminal appendix represents the most generalized, degradation 

 to two and then to one wing cell results in Groups B and C. the 

 former first having a submarginal wing vein, then losing that. 



** Not counting the supernumerary cell. 



