Il8 CONNECTICUT GEOL. AND NAT. HIST. SURVEY [Bull. 



"Length : 38 mm., including abdominal appendages ; tarsi 3-3-3 ; 

 antennae 7-jointed." 



Adult, male. — Color gray with a bluish tint (lilac), sometimes 

 with yellow. 



Head : face pale, anteclypeus black, ventral margin and median 

 spot on labrum, black ; labium with bifid mentum ; no postocellar 

 ridge or occipital ridge as in Gomphidae ; occiput pale with a black 

 transverse stripe. 



Thorax : mostly bluish gray, obscurely marked with brown ; 

 darker stripes on meso- and metapleural sutures and lateral carinae 

 between venter and metepimera; wings with a long stigma 8-9.5 

 mm. long by less than i mm. wide; triangle with i to 2 cross- 

 veins in front and hind wings, sectors of arculus (M3 and M4) 

 well separated, the caudal section of the arculus longer. 



Abdomen: terga 1-2 pale, pilose; 2 with 4 dark dorsal spots 

 and a lateral spot on each side, caudal margin black ; 3 with 2 

 dorsal spots and lateral margin pale; 4 with 2 dorsal black spots 

 and black lateral margins, the caudal spot much wider ; 3-7 similar 

 to 4, the dark marks connecting with the blacker caudal margin ; 

 terga 8, 9 and 10 almost entirely black, obscurely pale; a trans- 

 verse carina on terga 2-7 inclusive; anal appendages black or 

 dark brown (Fig. 24, Nos. 2, 3). 



Female. — With a broad well-developed ovipositor (Fig. 24, 

 No. i). 



Measurements: total length, male 72-75, female 75 mm.; 

 length of abdomen, male 50-58, female 54-55 mm. ; length of 

 hind wings, male 50-51, female 51-53 mm.; width of hind wings, 

 male 15-16 mm. 



Family CORDULEGASTERIDAE 



This family is represented in the northeastern United States by 

 a single genus, Cordulegaster. The adults are relatively slow 

 fliers, and the nymphs inhabit small streams. 



Genus Cordulegaster Leach 



The nymphs differ from all others in the characters of the 

 labium, the labial palpi being provided with large teeth on the 

 mesal margin; and the median lobe with two large teeth on the 

 distal margin (Fig. 7, No. i). 



In the adult the triangle is similar in both wings, and the super- 

 triangle is frequently without cross-veins ; the stigma is supported 

 by a cross-vein at its proximal end, the cross-vein being only 

 slightly obUque; M3 and M4 are well separated at the arculus; 

 anal margin of the hind wings of the male angular ; female pro- 

 vided with a very long ovipositor, and the thorax with three con- 

 spicuous yellow stripes on each side. 



