30 DRAGONFLIES OF OHIO. 



abdomen somewhat broader. The sides of 9 and 10 

 are bluish, there is more or less of an apical spot on 8 

 and the posterior border of 10, both blue. The green 

 on 7-10 both sexes is obscured with blackish. 



The posterior border of the prothorax of the male is 

 faintl\^ lobed ; on either side there is a shallow sinus 

 and in the middle a broad process \vith its upper 

 border sinuate. That of the female has three large, 

 round lobes, subequal. the middle rounder 



The posterior border of 10 is excised, denticulate in 

 the male. The superior appendages are very short, 

 black, with two branches; the upper outer one is 

 broad, obtuse, hairy; the lower more cylindrical, 

 slenderer, apex obtuse; these branches are somewhat 

 twisted on each other like the parts of the beak of the 

 cross bill; the lower branch appears to be movabl}' 

 articulated to the upper. The inferior appendages are 

 a little longer, turned upward and inward ending in 

 a black denticle. The female appendages are short, 

 thick, cones, yellow ; the ovate valves are 3'ellow with 

 black processes. 



It occurs about cool springs and streams of cool 

 quiet water in mid-summer. 



Nehalennia posita, Hagen. 



Length : of abdomen d 19, ? 19 ; of hind wing of d 

 12, ? 14.^ 



Blackish bronze marked with bright yellow or 

 greenish yellow. The anterior border of the frons, base 

 of antennae, gense, anterior half of labrum, under parts 

 of head, humeral stripe which is interrupted, sides of 

 thorax, anterior border and sides of prothorax, legs, 

 under parts and sides of abdomen, apical ring on 1, basal 

 rings on 2-7, and geminate basal spot on 9 yellow. 



The postocular spots are round and greenish yellow; 

 the second lateral suture is black; there are also black 

 stripes on the legs and rings on the tarsi. 



