The Odonala or Dragonflies of South Africa. 299 



1. No light-coloureil postocular spots. Thoracic dorsum bronze black without 



ante-hiiiiieral stripes .......... 2. 



Light-coloured postocular spots pi'esent. Thoracic dorsum mostly with 

 ante-humeral stripes -i. 



2. Lalivuin and frons anteriorly olive-green. Pterostigma greyish brown. 



Superior appendages with an acute sub-basal medial tooth furcigermn. 

 Labrum and frons bright orange-yellow. Pterostigma carmine. Proximal 

 .sub-basal median tooth of superior appendages truncate . . raffrum. 



3. Postocular spots round or transversely oval, often united by a line along the 



occipital margin. Frons black anteriorly to the postocular spots, at 

 least to base of antennae .... .... 4. 



Postocular spots very large, mostly reddish, lined anteriorly at most by a 

 narrow black band, the dorsal sul-face of head being thus chiefly red. 

 Superior appendages not distinctly furcate 7. 



4. Thoracic dorsum and abdomen of adult specimens more or less pruinose 



blue ; light markings bluish or greenish ; postocular sjjots separate. 

 Comparatively robust species ........ 5. 



^o pruinosity on thorax and abdomen of adult specimens. Light markings 

 on head reddish or orange, on thorax shading from yellowish to bluish. 

 Postocular spots united by a transverse line. Very slender form. Dorsal 

 branch of superior appendages in lateral view much narrower than 

 ventral one, slightly hooked. Pterostigma reddish brown angolense. 



5. Labrum dxiU olive-green or bluish ........ 6. 



Labrum deep black. Ante-humeral stripes broad, greenish in more or less 

 immature specimens, pruinose blue in adults. In superior appendages 

 viewed laterally the venti'al branch projecting a long way beyond the 

 dorsal one .......... praetextatum. 



(>. Thoracic dorsum entirely bronzy black with slight greyish pruinosity ; at 

 most a very slight indication of ante-humeral lines. Branches of 

 superior appendages in lateral view of almost equal length, the dorsal 

 slightly more obtuse than the ventral one. Pterostigma blackish. 

 Smaller species ......... salishuryense. 



Thoracic dorsum pruinose blue ; close to the humeral suture a narrow, 

 somewhat irregular, sometimes interrupted greenish or olivaceous line. 

 Superior apjjendages in lateral view, with the ventral branch obliquely 

 ascending as a rather narrow border to the somewhat shorter and 

 rounded dorsal branch. Pterostigma dull red. Largest species of the 

 present fauna .......... natalensc. 



7. Postocular spots entirely bordered with black. Dorsum of second abdominal 



segment predominantly black K. 



Postocular spots only partially and sometimes incompletely bordered with 

 black, confluent to the concolorous occiput or frons. Dorsum of second 

 abdominal segment predominantly blue, with a U-shaped black mark 

 Black lines of thoracic sutures very narrow .... ncaciae. 



8. Comparatively short and robust species, in size much like the preceding 



' one. Black lines of thoracic median and humeral sutures comparatively 

 broad ami sinuate. Dorsum of second abdominal segment black 



including one or two bluish points massaicum. 



Slender and more elongate species. Black lines of thoracic sutures narrow 

 Dorsum of second abdominal segment black .... sfostedti 



