568 

 Key to Species 



NYMPHS 



a. Gills with four distinct arcuate cross-bands and a blotch on the tip 

 of the gill; dorsal marginal setae of the median gill extending one- 

 third the length of the gill from the base ; lateral setae of the labium, 



five posita. 



aa. Grills with one or two cross-bands or none, never with four ; dorsal 

 marginal setae of the median gill extending one-half the length of the 

 gill from the base ; lateral setae of the labium usually six . . verticalis. 



ADULTS 



a. Mesopleural pale stripe of the supraepisterna interrupted at the caudal 

 third and fomiing a distinct exclamation point; eighth sternum of 



the female with a long spine posita. 



aa. Mesopleural pale stripe of the supraepisterna not interrupted at the 

 caudal third and not forming a distinct exclamation point; eighth 

 sternum of the female Avithout a long spine. 



b. Seventh tergum with more or less blue on the dorsum. . . .kellicotti. 

 bb. Seventh tergum black on the dorsum verticalis. 



IsCHNURA KELucoTTi Willlamson 



Nymph. — Unknown. 



Adult; Male. — Color, blue and black. 



Head blue and black; labium pale buff, the median lobe subtri- 

 angular; labial palpi broad, the second segment pale; antennae dark 

 brown, with a small pale blue spot on the condyle of the scape ; post- 

 clypeus black, anteclypeus blue; labrum blue except a black dorsal 

 marginal line; exposed portions of the mandibles, their trochantins, 

 genae, and the front above the fronto-clypeal suture to the antennal 

 fossae, blue; the blue area of the front is divided by a short black line 

 on the meson and the blue color extends dorsad above the genae to 

 the antennal fossae; remainder of the front and the vertex black; 

 postocular spots large and blue and connected with the blue of the 

 occiput ; occiput and postgenae except medium-sized black spots on 

 each side of the occipital foramen, pale blue. 



Thorax blue and black ; pronotum largely black, the cephalic lobe, 

 caudal margin of the caudal lobe, and four small spots on the median 

 lobe, near the meson, blue; proepimera blue and black, the caudal 

 half being largely blue; mesostigmal plates with blue lateral angles; 

 mesothorax w'ith black supraepisterna which possess narrow longi- 

 tudinal blue stripes, the stripes narrowed conspicuously at the middle 



