114 DRAGONFLIES [CH. IV 



(29) 2. Family A. LIBELLULID^E. The triangle of the fore-wing 

 lies transversely to the length of the wing itself. Sub- 

 families included are Libellulince and Corduliince. 

 (22) 3. Sub-family LIBELLULIN.E. 2nd abdominal segment of 

 males simple, inner margin of hind-wing in this sex 

 straight or convex, not concave. Appendages of 10th 

 abdominal segment of male simple, of female cylindrical 

 or fusiform, not flattened. Abdomen not bronzy in 

 colour. 



genera Leucorrhinia^ Libellula, Sympetrum, Orthetrum. 

 (10) 4. Hind- wings with triangular dark spot at base. 

 (6) 5. genus Leucorrhinia. Abdomen with mid-dorsal spots, 

 parallel-sided. Sole British species Leucorrhinia dubia, 

 Lind. <$ black with crimson spots, 9 black with yellow 

 spots. Length ^ 35'5 39mm., $ 34 36mm. Expanse 

 of wings $ 53 58 mm., $ 52 55 mm. 

 (5) 6. genus Libellula. Abdomen not spotted dorsally, sides 



not parallel. 

 3 species : 



(8, 9) 7. L. quadrimaculata, Linn. Wings with a black spot at 

 the node. Length $ 39 47 mm., $ 41 47 mm. Ex- 

 panse of wings ( 64 74 mm., $ 70 80 mm. 

 (9) 8. L. depressa, Linn. Fore-wings with oblong dark patch at 

 base, hind-wings with large triangular dark patch at 

 base. Abdomen of <J steely blue, $ yellow-brown. 

 Length 47 mm., $ 42 44 mm. Expanse of wings 

 c 75mm., $ 75 78mm. 



(8) 9. L. fulva, Miill. Fore-wings with 2 dark lines at base, 

 hind-wings with 1 dark line and small dark triangular 

 patch at base. Abdomen of < steely blue with black 

 streaks, of $ tawny with blue-black central markings 

 on hinder segments. Length $ 44 mm., $ 45 mm. 

 Expanse of wings 74 mm., 9 75 mm. 

 (4) 10. Wings not spotted. 

 (19)11. genus Sympetrum. Antecubital nervures about 7. Male 



red or black. 

 5 species : 

 (16) 12. Legs yellow. 



