I 24 BritisJi Dragoi/Jlies. 



part of the segment. Anal appcndag-cs black ; upper 

 ones CN'linclrical, pointed, as long as the last segment 

 but one ; lower triangular, turned up at the tip. 



Female Imago. 



Head and thorax much the same as the male but 

 lighter, and cjuite without blue powdering. Eyes brown. 

 Legs brown. ]Vi)igs suffused with saffron towards the 

 costal margin. Abdomen )-ellowish-brown fin \er\' old 

 specimens dark brown j, rounder than in male, dorsal keel 

 and margins of segments dark brown, trans\erse 

 posterior lines meet in this sex and broaden, forming a 

 black mid-dorsal transverse streak, through which the 

 keel passes. Anal a/>/>endages c}'lindrical, pointed, about 

 as long as the tenth segment, pale brown. ]^ulvar 

 scale notched at the tip, the points swollen. Sides of 

 eighth and ninth segments forming a kind of wxwg below. 



Immature Colour. 



When immature, the male closclx' resembles the female 

 in tint. The cerulean bloom appears after a time on 

 the abdomen, and usuall}' spreads inore or less o\-er 

 the thora.x, the parts not blue becoming darker. The 

 surface of the immature abdomen is gioss)-. 



Variation. 



In the British Isles this insect does not seem to var\- 

 ver}' much — not e\-en in size. The dark coloin- of the 

 abdomen of the female and of the wings of both sexes, 

 observed late in the season, are simpl}- due to age. On 

 the Continent blue-bodied females and males with dark 

 pterostigmata ha\e been noticed, these changes also 

 haxintr been caused no doubt b\- a""e. 



