

CH. IV J DRAGONFLIES 119 



10th abdominal segment of the male has two ventral 

 appendages. 



This group includes only the Family Agrionidce. 



Family AGRIONIDCE. This being the only family repre- 

 senting the Zygopterids the characters of the group 

 serve also for the family. Sub-families included are 

 Calopterygince, Agrionince. 



(55) 52. Sub-family CALOPTERYGIN^. Antecubital nervures nu- 

 merous: wings coloured, pterostigma of female white; 

 male with no pterostigma. Sole British genus Calopteryx. 

 genus Calopteryx. (Characters of sub-family.) 

 2 species : 



(54) 53. C. virgo, Linn. Wings of almost completely blue, of 

 9 brown with bluish sheen. Length of 45 47*5 mm., 

 of $ 43 46 mm. Expanse of wings $ 56'5 62 mm., 



9 58-5 69mm. 



(53) 54. C. splendens, Harr. Wings of $ with blue patch across 



centre only, of $ greenish and pterostigma near tip of 



wing. 

 (52) 55. Sub-family AGRIONIN^E. Antecubital nervures only 2. 



Wings not coloured : pterostigma dark and in both sexes, 

 genera Lestes, Erythromma, Pyrrhosoma, Ischnura, Platy- 



cknemis, Agrion, Enallagma. 

 (65) 56. No blue spot behind eyes. 

 (62) 57. Abdomen not crimson. 

 (61) 58. genus Lestes. Abdomen of $ with segments 1, 2, 9 and 



10 blue, remainder green. Eyes blue. 

 2 species : 



(60) 59. L. dryas, Kirby. Rather robust : expanse of wings in 

 both sexes considerably greater than length of body: 

 pterostigma relatively broad. Dorsal anal appendages 

 of with broad inwardly directed flange extending 

 of length and bearing a narrow sharp tooth at about ^ 

 from base: distal $ of appendages broadly spatulate, 

 turned sharply towards each other. Ventral anal ap- 

 pendages of < barely half as long as dorsal and incurved. 

 Black spots on dorsal surface of 1st abdominal segment 



