449 



Tabular Summary — continued 



Paleodictyoptera 



Protodonata 



Odonata 



Dictyoneuridae 



Meganeiiridac 



Protagrionidae 



Paralogidae 



Anisozygoptera 

 Arehizygoptera 



No quadrangle 

 triangles 



or No quadrangle 

 triangles 



Zygoptera 

 Anisoptera 



Three simple anal 

 veins present 



Anal field not exten 

 sively developed 



Head rounded ; of 

 considerable size 



Not known 

 Not known 

 Not known 



Not known 



or Q u a d r a n gle and 

 sometimes trian- 

 gles present 



Anal veins represent- 

 ed by a single 

 vein 



Anal field not exten- 

 sively developed 



Large numbers of 

 rows of cells be 

 tween all longi- 

 tudinal veins, the 

 rows extending far 

 proximad 



Not known 



Not known 

 Not known 

 Not known 



Not known 



Anal veins repre- 

 sented by a single 

 vein 



Anal field often ex- 

 tended, but not 

 braced by loop 



Decided reduction in 

 number of rows 

 and a decided re- 

 treat distad, leav- 

 ing but few rows 

 between the prox- 

 imal portions 



Head rounded and 

 of c n s i derable 

 size 



Eyes dichoptic in all 

 families 



Labium cleft 



Abdomen s I e n der, 

 occasionally swol- 

 len at tip; superi- 

 ors leaf-like or 

 forcipate 



Inferior anal ap- 

 pendages separate 



Quadrangle always 

 present ; triangles 

 sometimes present. 



Anal veins repre- 

 sented by a single 

 vein. 



Anal field extensively 

 developed or re- 

 duced ; when ex- 

 tended often 

 braced by loop. 



Still further reduc- 

 tion and retreat 

 distad. 



Head angular; often 

 widened. 



Eyes dichoptic or 

 holoptic. 



Labium cleft or en- 

 tire. 



Abdomen s 1 e n d er, 

 Zygoptera, or 

 thickened, Anisop- 

 tera ; s u p e r i rs 

 leaf-like, forcipate, 

 or reduced to tu- 

 bercles. 



Inferior anals fre- 

 quently united in 

 Anisoptera. 



