The Odonata or Drarinnfies of South Africa. 387 



Double cui-ve of M., very deep. In hind wing cells between A^ and 

 wing's edge distinctly disposed in transverse row's, t in front wings 

 mostly with two cross-veins, crossed in hind wings. Mostly 4 rows in 

 discoidal field of front wings ; 2-3 rows Rs-Rspl and Mf-Mspl. 

 Angles of frous projecting, acute. General forms as in preceding genus, 

 also genital segments of female. No triangular flattened spaces on 

 anterior surface of frons ....... Bradinopyga. 



13. Number of ^»H7 small, mostly under 8. (Plate XI, fig. -1) . .14. 



Number of Anq greater, more than 8, mostly over 10. Hind lobe of pro- 

 thorax small. (PlateXI, fig. 5) ■ . .16. 



14. Hind lobe of prothorax large, bilobate, erect, ciliate. Cw, in front wing 



but feebly convex. Abdomen comparatively short, more or less fusiform 

 in male, cylindrical in female. Margins of eighth segment folded in 

 female ; vulvar scale variable ........ 15. 



Hind lobe of prothorax small. Fovirth segment of abdomen with distinct 

 transverse carina. Discoidal field in front wing approximately parallel, 

 by Cui and .1/^ being about equally convex. In front wing costal side of 

 t long, t free or crossed. Cmj in hind wing variable, at anal angle of 

 t or separate. Abdomen short and robust ; depressed in male, more 

 cylindrical in female. 



In female margins of eighth segment folded, small but distinct vulvar 

 scale ; ventral plate of ninth segment broad . . Brachythemis. 



15. / in front wing crossed, costal side comparatively long. Discoidal field 



beginning with 3 rows of cells, distinctly narrowed to wing's edge. Cu^ 

 in hind wing at anal angle of t : cells between A-j and wing's edge not 

 disposed in transverse rows. (Plate XI, fig. 4) . . . Sympetrmn. 

 t in front wing free, costal side short. Discoidal field mostly beginning 

 with two large cells, then 3 rows ; almost jiarallel to wing's edge. C«, 

 in hind wing separate from anal angle of t ; cells between ^3 and wing's 

 edge distinctly disposed in transverse rows . . . Philonomon. 



16. Anal loop in hind wing long, external angle 3 4 cells' distance beyond level 



of distal angle of t. Large forms ....... 17. 



Anal loop in hind wing shorter, external angle a))OUt 2 cells' distance 

 beyond level of distal angle of t. 



Medium sized and smaller forms. Bs straight; Jlf.i convex in simple 

 curve or with very slight indication of double curve. 2 rows Rs-Rspl. 

 Discoidal field in front wing between almost jiarallel veins or slightly 

 narrowed to wing's edge. C'li, almost straight. (Plate XI, fig. 5.) 

 Pterostigma small. Colour system red with various mixture of black, 

 or black and yellow, with or without blue pruinosity. Abdomen variable. 



Trithemis. 



17. Spines of tibiae fine. Pterostigma comparatively small. Moderate or deep 



double curve of M.,. Colour system black and yellow, often metallic. 



Abdomen variable Paeudomacromia. 



Spines of tibiae robust. Pterostigma large. Very deep double curve of 



Mn. Colour system as in preceding genus. 



Abdomen much inflated in basal segments, very slender hindward. 



Olpogastra. 



