Agrion. 



293 



their peculiar shape will be seen from Fig. 51, the 

 roundish lobe being blue, the rest chiefl\' black. The 

 spot on the second segment somewhat resembles that 



Fig. 51. — Anal Appkndagk.s of Male of Agrion Mercuri.\le. 



Dorsal and Ventral View. 

 (After Hagen, in De Selys' "Revue.") 



on the second segment of the female of A. piilcJiellinn, 

 but the size and the sex should determine the species. 



Female Imago. 



In the female the blue colouring is replaced by 

 greyish-green, except for the hinder edge of the seventh 

 and eighth segments, which is in each case bright 

 blue. The black-bronze spots nearly fill the dorsal sur- 

 face, except a band along the anterior edge : the spot 

 on the second segment is thistle-shaped ; the centre of 

 the pterostigma is rather pale brown. The smaller size, the 

 circular spot behind the eyes and the blue margin to 

 the seventh and eighth segments should be sufficient to 

 distinguish the female of this species from that of 

 A. puclla^ which it in other respects closely resembles. 



Immature Colouring. 



The male passes through the same yellow, grey and 



