370 Annals of the South African Museum. 



Anax tristis (Hagen, 1867). 



S. Afr. Mus. : 1 (^ , Bulawayo, Ehodesia ; Grootfoutein, S.W. 

 Protectorate (i . 1919, Liyhtfoot). Mus. Bruxelles : 1 ? , Kiuchassa 

 (26 . X . 1899, Waelbroeck). Mus. Tervuereu : 1 ? , Kiamhi (19 . ii . 

 1911, B. Valdouis); 1 J, Kunga (iii . 1913, Verschuereu). Mus. 

 Hamburg: 1,^, Quitta, W. Africa (J. Cordis). 



(J . Labium and labrum dull ferruginous, gradually passing to 

 blackish at free margins. Face and frous light green ; at base of 

 frons a triangular black margin, the obtuse angle of which reaches 

 to half-way between base and anterior ridge. Thorax light green, 

 latero-veutral sutures marked with dull ferruginous. Legs black, 

 femora dull ferruginous at exti'eme base. Al)domeu inflated at base, 

 considerably contracted in segment 3, almost cylindrical, rather 

 slender from end of 3 to 7, gradually widened to the end, to be 

 broadest at segment 9. Segments 3-6 very long, 10 strongly convex 

 dorsally, almost globose. Segments 1-2 light green, terminal joints 

 lined with black, a broad liilobate black spot on dor.sum of 2 ; 

 3 green to transverse carina, black posteriorly, this colour projecting 

 almost to anterior margin in a narrow mid-dorsal line : 4-7 lilack, 

 each side with a rouuded light green spot at both ends, the anterior 

 sjiots slightly larger on 4-5, the j)osterior ones on 6-7 ; 8-9 black 

 with only the jjosterior green spots ; 10 wholly black. Appendages 

 dark brown ; superiors nearly straight at lateral margin, the median 

 margin triangularly projecting with angle slightly beyond the middle; 

 apex truncate, medially rounded, laterally produced in a short point 

 which is the end of the dorsal carina ; distal half of median margin 

 densely covei-ed with long Ijrowu puljescence. Inferior appendage 

 nearly two-fifths longer than the superior, broadly triangular, 

 truncate and slightly emarginate. Wings hyaline ; at base of the 

 posterior a dark golden-brown spot along the membranule ; slightly 

 beyond the triangle, between Jf, and anal margin, a diffuse light- 

 brown cloud. Costal vein with a yellowish line ; pterostigma dark 

 brown on upjjer, ochreous on under side of wing. Membranule white 

 in proximal third, black in distal two-thirds. 



9 . Exactly similar to male in colour. Abdominal segments 3-6 

 much less elongate. Appendages comparatively short, foliaceous, 

 elliptic in outline. 



J. ■ Abd. 84 -f 6-0, hdw. 61, pt. < 6 mm. 5 , 70 + 4, 63, < 6. 



This wonderful insect is one of the largest dragonflies, the female 

 of otherwise regular proportions, the male conspicuous by the greatly 

 elongate alidomen. No doubt it is a powerful flier, and it would be 

 of interest to learn something regarding its habits and liehaviour. 



