26 



(1. Antennae 4-jointed, broad and flat, superior appendage 



not notched at apex. Gomphidce. 



c. Labium spoon-shaped, covering most of the face, with 



subtriangular close-fitting lobes. 



ff. Teeth on the opposed edges of the lateral labial lobes 



acute, very large and irregular, interlocking; two 



stout teeth with a cleft Ijetween them at the apex 



of the median lobe. Conli(Ie(jasferida'. 



f. Opposed edges of the lateral labial lobes crenate or with 



rounded teeth ; at most but a single median 



tooth on median lobe. LlheUuUdce' 



Imafios. 



aa. Front and hind wings similar, or nearly so, in outline, usu- 

 ally elevated when at rest; males with two inferior 

 abdominal appendages {Zygoptera). Head transversely 

 elongated, eyes widely separated. Females with genital 

 valves. 

 hi). Not less than five antecubital cross-veins in the an- 

 terior series. Calopterygidw. 

 h. Not more than three antecubitals, usually two. 



Agn'onidce. 

 a. Front and hind wings dissimilar, hind wings usually much 

 broader at the base, horizontal when at rest ; males with 

 one inferior ax^pendage, or none. {AnisojjfenL) 

 cc. Triangles of front and hind wings of similar shape ; 

 antecubitals of first and second series not coinci- 

 dent, except the first and another thick one ; second 

 series of postcubitals complete. 

 d(L Abdomen with lateral carinas ; female with genital 

 valves ; head globose, eyes meeting above along the 

 middle line of the head. jEsrhnida'. 



d. Abdomen without lateral carinae. 

 ff. Eyes distinctly separated, head transversely elongated. 

 gg. Median labial lobe bifid ; female with genital 

 valves. Fftaluridce. 



