The Odoiiata or Drngonflies .,/ South Africa. 345 



Segments 1-7 dull olivaceous, obscure markings small and rather 

 diffuse : basal half of segment 1 ; lateral and dorsolateral bands on 

 2 ; narrow ring at anterior transverse carina, broader terminal ring 

 and indistinct lateral and posterior spots on 3-6 ; 7 greenish on 

 anterior, dull ferruginous on posterior half ; 8-10 ferruginous, dila- 

 tations of 8-9 darker to almost black. 



Fia. iT.^Mesogomphus Hageni, $. Eritra. Genitals, second segment, 

 left side view. 



Appendages ochreous. Text-fig. 46. Genital organs of second 

 segment, Text-fig. 47. 



Wings hyaline, lightly tinged with greenish yellow in very adult 

 specimens ; costa yellow to base of pterostigma ; pterostigma, see p. 343. 

 9 . Very similar to male. No structural differences in vertex and 

 occipital plate. Abdomen considerably more robust ; terminal abdo- 

 minal segments comparatively less dilated. Appendages longer than 

 tenth segment, very fine and pointed, light yellowish, tips black 



Fio. 48. — Mesogomphus Bageni, ?. Waterval. Terminal segments 

 ventral view. 



Ventral plate of ninth segment concave, the cavity bordered near the 

 segment's end by a sharp, almost semicircular ridge. Vulvar scale 

 slightly less than one-half the length of segment '?, roughly triangular 

 in outline, excised (Text-fig. 48). 



(J, Ahd. 31 + 3, hdir. 23, 2}f. 3 mm. ? , 32, 20, 3 (Waterval). 



■ S , ^bd. 28 + 3, hdw. 22, j}*. 2-5 mm. (Eritrea). 9 , 32, 27, 3 (Harrar). 



No apprecial)le differences in structure or colour exist lietweeu 

 South African, Abyssinian and Algerian specimens of this wide- 

 ranging sj)ecies. 



