No. 39] ODONATA OF CONNECTICUT: LIBELLULIDAE 277 



the female venter projecting below on segment 8 ; the males are 

 easily separated by means of the appendages. 



Connecticut.— New Haven, 12 August, 1902 (B. H. W.), 16, 21 October, 

 1903 (H. L. v.). 26 July, 1906 (P. L. B.), 21 July, 1920 (P. G.) ; 

 Stonington, 25 July, 1906 (J. A. H.) ; Storrs, 5 October, 1923 (J. Cronin). 

 Common throughout the State. 



New England. — June 24-November 8. 



Genus Pachydiplax Brauer 



Nymphs. — Labium with 10 lateral setae on palpi, and about 12 

 on mentum ; abdomen without dorsal hooks, the lateral spines on 

 segments 8 and 9 long (that on 9 extending beyond segment 10), 

 and similar in size and shape ; superior anal appendages not 

 decurved. 



Adults. — Wings with less than ten antenodal cross-veins; 

 stigma with parallel proximal and distal margins, three times as 

 long as broad, supported by o-i cross-veins ; triangle three-sided, 

 considerably further distad in the front wing than in the hind ; 

 M, not sinuate ; subtriangle absent ; Cu, not arising exactly from 

 the caudal angle of the triangle in the hind wings, but from the 

 distal side ; caudal margin of the pronotum bilobed, and with long 

 hairs ; all femora with two ventral rows of short spines ; male 

 abdomen without ventral hooks on the first segment ; transverse 

 median carinae on abdominal terga 2 and 3 ; general color green, 

 black and yellow. 



Similar in habits to the Libellulas. 



Pachydiplax longipennis (Burmeister) 



Handbuch der Entomologie, 2: 850: 1839. 



Nymph. — Color brown or greenish, shape similar to Sympe- 

 trum. 



Head : labium with very shallow teeth, dorsum of the head 

 smooth; 10 setae on the palpi and about 12 on each side of the 

 mentum. 



Thorax : legs slender, the femora usually with three dark rings. 



Abdomen : entirely without dorsal spines, but with large lateral 

 spines on segments 8 and 9, the spine on 9 extending well beyond 

 the caudal margins of segment 10. 



Measurements: total length, 16-19 mm.; length of abdomen, 

 9 mm. ; greatest width of abdomen, 7 mm. ; length of hind femora, 

 4 mm. 



These measurements were made from exuviae in the Museum 

 of Comparative Zoology. Needham's measurements (Bull 47, 

 N. Y. State Museum, page 527) are somewhat larger, the total 

 length being 21 mm., and the length of the femora, 6 mm. 



Adult, male. — Color dark brown or green to black with greenish 

 yellow stripes on thorax and abdomen. 



