42 DRAGONFLIES OF OHIO. 



narrower (more abruptly and deeply on the inner side) 

 then expand to a broad, truncated slightly concave 

 termination, a pale, depressed tubercle projects 

 beyond giving a convex outline, the inner angle of the 

 chitinous part is acute and slightly recurved; cephalad 

 of this angle the anterior end of the obliquely placed, 

 compressed, pale tubercle projects at an obtuse angle: 

 in profile the appendage has the upper and lower sides 

 nearly parallel, the end truncated at nearly a right 

 angle with edges rounded, the tubercle projecting 

 below and beyond making the outline rounded and 

 projecting upward beyond the upper truncation. The 

 inferiors are light at base, black at apex, rather slender 

 shorter than the superiors, directed upward, base 

 broad concave or sinuous below. 



The appendages of the female are dark brown, 

 conical. 



The species has been taken at Columbus in May. 



Enallagma exsulans, Hagen. 



Length : of abdomen cT 27, 9 26 ; hind wing of o 71 18, 

 9 20. 



The male is bright blue and black. The head is 

 black above with wedged-shaped, connected postocular 

 spots blue, face blue with post-clypeus and a transverse 

 band at base of labrum black ; prothorax black with 

 transverse line in front, the sides, spots upon the post- 

 erior border, a triangular spot each side of the dorsum, 

 and a geminate oblong one between them ; thorax blue 

 with wide mid-dorsal, and numerals black, legs black 

 with pale stripes, tarsi pale with dark rings ; pteros- 

 tigma brown pale edged. Abdomen slender, blue with 

 black on the dorsum as follows : much of 1, a narrow 

 band on 2 widest apically, the whole of 3-7, except in- 

 terrupted apical rings, a narrow band on 8 not reaching 

 the apical border, and on 10 often much narrowed post- 

 eriorly. The female is green and black ; head and pro- 



