533 



femora with stripes on the dorsum, the tibiae with black stripes occupy- 

 ing half the dorsa, but not reaching the apices of the segments ; tarsi 

 and claws pale, dark at the tip, the claws notched at a considerable dis- 

 tance proximad of the tip ; wings with nine or ten postnodal cross-veins, 

 the vein M 2 arising between the fourth and fifth postnodal cross-veins, 

 usually near the fifth, in the front wing, and between the fourth and 

 fifth in the hind wing. 



Abdomen blue and black, the cephalic terga largely blue, the 

 caudal ones darker and frequently becoming pollinose with age ; terga 

 1-6, inclusive, blue except a small basal spot on the dorsum of one and 

 black shield-shaped apical spots and apical rings on 2-6; dorsal black 

 spot of the sixth tergum occupying about half the dorsum, those of 

 2-5 about one-fourth; dorsum of the seventh and tenth terga black 

 except the lateral margins and a narrow, basal, interrupted ring on the 

 seventh ; all of the eighth and ninth terga blue ; sterna 2-10 with a black 

 median line; anal appendages (Figs. 198, 103) short, the superiors 

 blunt, with a narrow cleft or notch just ventrad of the apex ; inferiors 

 usually black and shorter, the black tips directed obliquely caudad and 

 dorsad and frequently in contact with the superiors. 



Female. — Color similar to that of the male. 



Head similar to that of the male. 



Thorax similar to that of the male except in the color of the legs, 

 which are usually lighter, the dorsal stripes of the femora never ex- 

 tending to the proximal ends of those segments. 



Abdomen : the dorsum of all terga have a black longitudinal stripe 

 from the bases to the apices and a short, narrow, apical, black ring; 

 margins of all terga yellow or blue, the pale color extending onto the 

 dorsum at the bases of segments 2-6, but always forming interrupted 

 rings and never connected across the dorsum (Fig. 92) as in caruu- 

 culatum (Fig. 91) ; sterna 1-8 with a mesal line from bases to apices, 

 the apex of the eighth sternum with a heavy seta which is darker at 

 the tip than at the base; anal appendages of the usual form, the ovi- 

 positor with yellow lateral valves, the ventral margins of which are 

 serrate from the apex to near the base ; prostyles brown, dark at the tip. 



Measurements 



Length, $ 29-32 mm. 



Length, $ 30-32 mm. 



Length of abdomen, $ 23-24 mm. 



Length of abdomen, 9 23-24 mm. 



Length of hind wings, $ 17 mm. 



Length of hind wings, $ 19-20 mm. 



Width of hind wings, $ 3.5-4 mm. 



Width of hind wings, $ 3.5-4 mm. 



1 



