58 



British Dragonflies. 



Pterostigma not \qx\ narrow; anal angle 

 of hind-wing of male distinctly ]iointed : 

 lower anal appendage of male jiointed . . ^schna. 



[Sub-Family Calopterygin.!':.] 

 Characters of sub-family 



[Sub-Family Agrionin.?;.] 



A. Abdomen with segments i, 2, 9, 10 blue in 



male ; whole abdomen bron/x'-green in 

 female 



a. Eyes blue ; rest of abdomen of male green 

 h. Eyes red ; rest of abdomen of male steel- 

 black 



B. Abdomen crimson, with bronze markings 



C. Abdomen black ; segments 8 or 9 blue in male ; 



a circular blue spot behind eyes ; small 

 apical ventral spine on 8 in female ; ptero- 

 stigma of male darker on fore-wings than 

 on hind ; nodal sector arising at fourth post- 

 cubital on fore-wings, third on hind-wings 



D. Abdomen of male blue, marked with black. 



a. Alid and hind tibia? dilated, whitish, margins 

 with long black spines 



h. Tibia; not dilated ; a pear-shaped blue spot 

 behind eyes. 



1. No apical ventral sjiine on 8 in female; 

 pterostigma similar on fore- and hind- 

 wings ; nodal sector as in Enallagma 

 (except fnermriale) 



2. Distinct apical ventral spine on 8 in 

 female ; pterostigma similar on fore- 

 and hind-wings ; nodal sector arising 

 near fifth post-cubital on fore-wings, 

 fourth on hind-wings (or more remote) . 



Calopteryx. 



Lestes. 



Erythromma. 

 Pyrrhosoma. 



Ischnura. 



Platychnemis. 



Agrion. 



Enallagma. 



IV. — Table of Species. 



Leucorrhinia, Cordulia, Oxygastra, Gomphus, Cordulegaster, 

 Anax, Brachytron, Platychnemis, and Erythromma, containing 

 each but one s|)ecies, the characters of the genus will determine the 

 species. 



