56 DRAGONFLIES OF OHIO. 



(a). Male and female occiput with a spine in the middle villosipes. 



(b). Without the occipital spines furcifer. 



(2). . Superior appendages brown, pointed, an acute tooth represent- 

 ing the outer distal angle. 



(a). From side view the male superior appendages have a strong, 

 acute tooth near the middle of the inner, inferior edge, 



spicatus. 



(b). From side view the male superior appendages have obtuse 

 prominence near the apex of the inner, inferior edge Hvidus. 



2. Small, male abdomen 30 mm.; antehumeral more divergent 

 below. 



(1). Face yellow, occiput straight exilis. 



VI. 



1. Large, black, 9 long spiniceps. 



2. Large, brown, 9 slightly longer than 8 plagiatus. 



VII. 

 1. Large, brown and yellow notatus. 



Group II. 

 Gomphus dilatatus, Rambur. 



Length : of abdomen cT 50, 9 47 ; of hind wing cT 

 40, 9 40. 



Male black and yellow ; head yellow, the following 

 black: borders of labrum and vertical line in the middle, 

 a transverse line between clypeus and frons, the vertex 

 antennae ; and the vertical vesicle is straight, occiput 

 rather narrow, convex with a fringe of black cilia. The 

 prothorax black, sides yellow with a large geminate spot 

 centrally of the same: the thorax is yellow, black as 

 follows: a mid-dorsal stripe with parallel sides, not 

 reaching the front margin, an ante-humeral and humeral 

 — both widely separated by a narrow yellow line and two 

 lines on the side ; legs black with coxae and under side 

 of fore tibiae yellow ; the wings are hyaline, costa 

 yellow ; pterostigma moderate covering five cells, 

 yellow surrounded by heavy black veins. The abdomen 

 is black, yellow as follows : sides of 1-2, dorsal band on 

 1-4, lanceolate apical spot on 5-7, large triangular 

 apical spot on side of 8 and oblong one on side of 9. 



