&74 



Abdomen shining black or green, and yellowish green; dorsum 

 of terga 1-7, inclusive, shining black or green with narrow apical ring 

 on the first, interrupted basal rings on 3-6, and the lateral margins 

 of 1-6 yellow; dorsum of terga eight and nine blue, with short lateral 

 black stripes on each side about half the length of the segment; tergum 

 ten black, the lateral margins pale, the caudal margin with a short 

 forked process on the meson ; sterna 3-9 with a mesal line of black ; 

 anal appendages (Fig. 168) short, the superiors flat and placed nearly 

 vertically ; inferiors longer, and with a dorsal, basal knob and a larger, 

 subcorneal ventral lobe. 



Female. — Color, orange and black or entirely black. 



Head similar to that of the male except that the yellowish green 

 markings are replaced with orange. 



Thorax orange and black ; pronotum with an orange spot on each 

 median lobe ; margin of the caudal lobe with orange spots ; mesostigmal 

 plates (Fig. 180) with caudal elevated margins orange in color; meso- 

 pleural pale stripe of the supraepisterna orange and much broader 

 than the pale stripe of the male ; dorsal third and caudal margin of 

 the mesinfraepisterna black, the remainder pale orange; metathorax 

 orange ; legs orange and black, the femora entirely pale except at the 

 tips, the tibiae with the usual dorsal stripes. 



Abdomen orange and black, the first two segments entirely pale 

 except a narrow ring on the caudal margin of the second ; terga three 

 orange with an apical spot and ring; dorsum of terga 4-8 black, with 

 pale basal rings on 4-6 and the apical third of eight also pale; terga 

 nine and ten indefinitely marked with black, there being an orange 

 spot and apical ring of orange on nine and a dorso-mesal line on the 

 same ; lateral margins of all the terga orange ; sterna 1-8, inclusive, 

 with a mesal black line, the eighth sternum with a heavy spine ; anal 

 appendages of the usual type; the ovipositor with dark brown pro- 

 styles and pale lateral valves. 



In older specimens the orange color becomes black and pollinose 

 so that it is difficult to distinguish the species on the wing from some 

 of the Enallagmas which also have a tendency to become dark. 



Measurements 



Length, $ 20 mm. 



Length, 2 30 mm. 



Length of abdomen, $ 22 mm. 



Length of abdomen, 9 23-24 mm. 



Length of hind wings, $ 14 mm. 



Length of hind wings, $ 17 mm. 



Width of hind wings, $ 3.5 mm. 



Width of hind wings, 2 3.5 mm. 



