310 PROCEEDINGS OF THE NATIONAL MUSEUM. vol.49. 



Thorax relative)}' large; wing pads held parallel and reaching to 

 the middle of the fourth abdominal segment. Legs long and sprawl- 

 ing. Abdomen conical, slender; the gills large, increasing in width 

 to the apical third, then rapidly reduced to an attenuate apex. 



The color pattern is complex, usually vivid, and is as follows: 

 Head black, with white area over location of adult median ocellus, 

 from which a stripe runs forward and a branch on either side runs 

 laterad of its eye and antenna. Postocular spots comma-shaped. 

 Eyes gray. Pro thorax white, with a black fleur-de-lis design. Coxae 

 and trochanters black, femora with two black bands and the distal 

 end black. Mesothorax and metathorax black, with middorsal pale 

 areas and the dorsal edges of the episterna light. A light spot on the 

 dorsal half of each infraepisternum. Legs banded as in the first 

 pair. Abdomen black, with a row of spots along the lateral keels, a 

 middorsal stripe, and a row of spots on each side midway between the 

 lateral keels and the middorsal stripe. Gills plain. 



This nymph differs from that of perparva in the longer legs, the 

 greater distance between the eyes, and the sharp banding of the legs. 



ISCHNURA PERPARVA Selys. 

 Figs. 81-86, 92, 93, 101-105, 110-116, 122-126. 



Ishnura perparva occurs <luring the entire odonate season and is 

 frequently as abundant along the stagnant side pools of fresh streams 

 as it ever is about alkaline ponds, where it occurs in equal abundance 

 with cervula. In other words, it seems to be adapted to a wider 

 variety of conditions than cervula. 



In habits it resembles cervula but, when at rest in copulation 

 (fig. 92), or ovipositing (fig. 93), the wings are usually held tightly 

 closed. Being a heavier bodied insect, the abdomen is seldom bent 

 into the U-shapes common with ovipositing cervula. As in cervula 

 the males rarely accompany the females while the latter are ovi- 

 positing. 



Male (figs. 81, 82, 101-104). — Labrum greenish, with black line 

 above. Frons greenish in front, black on horizontal surface. Entire 

 top of head black, except broad greenish band across front and small 

 greenish postocular spots. Antennae black. Eyes abruptly black 

 above, pale green below. 



Prothorax black above, except narrow greenish line along base of 

 anterior lobe and a small greenish spot on either side of the middle 

 lobe. Sides of prothorax, coxae, and legs yellowish green, with 

 femora broadly black on outer surface and a narrow stripe on outer 

 face of tibiae. 



Mesothorax and metathorax pale green, with broad middorsal 

 stripe and bcoad hunioral stripes. Legs colored as in first pair. 



