1 86 British Dragonflies. 



Female Imago. 



Blue colour of a whiter or more lavender tint than 

 in the male. Ptcrostigiiia brown ; a little over 4mm. 

 lony,". Anal angle of hind-wings rounded. Ovipositor 

 and valves reaching just beyond the ninth segment. 

 A)ial appendages small, lanceolate, rather pointed. 

 The shape of the abdomen is more like that of 

 the male than is the case with the other British 

 ^•Eschnas. 



Immature Colouring. 



The latel}^ disclosed male is of a general pale lilac 

 tint instead of blue, and then more closely resembles 

 the female. 



Variation. 



Great stress was at one time laid on the absence of 

 bifurcation in the subnodal sector brought forward by 

 De Selys ("Revue des Odonates," p. 122) — " . . . cette 

 derniere est la seule (avec \^-E. irene) parmi les Libcl- 

 lules d'Europe, dont le secteur subnodal n'est pas bifurque 

 sous la pterostigma." This character has, however^ 

 been found not alwa}'s to hold, and Mr. McLachlan 

 thus sums up the case"^ : " That the uj^per branch of the 

 furcation (when present) is perhaps ne\er in the solid 

 condition usual in ^■Eselina ; that it is often rudi- 

 mentary, and that it is often absent in some of the 

 four wings ; but in all the specimens in m)- collection 

 I do not find one in which there is not an indication 

 (at least) of furcation, sometimes onl)- on one side,, 

 sometimes in the anterior and not in the posterior. It 



* E. M. M., 1889, p. 273. 



