No. 39] ODONATA OF CONNECTICUT: AGRIONIDAE II3 



Adult, male (PL xvii, a). — Color metallic blue or green. 



Head : green or blue ; labium black, antennae black ; clypeus 

 and labrum metallic green or blue ; front together with the clypeus 

 and labrum thinly pilose ; eyes black or slate-colored. 



Thorax : green or blue above, black below ; pronotum with the 

 caudal lobe convex ; dorsal carina of mesothorax black ; paraptera 

 subquadrangular, the caudal margins emarginate or sinuate ; ven- 

 tral portion of the metepimera and the intersternum wholly black 

 and subshining ; legs black, the setae also black and longer than 

 the intervals between their bases; anterior femoral setae 14 or 15 

 on each side, tarsi black; wings very dark, almost opaque and 

 about one-third as wide as long (sometimes variable, parts of the 

 wing being smoky and not opaque) ; stigma wanting; antenodal 

 cross-veins 24-28. 



Abdomen: nearly cylindrical, glabrous, and striated trans- 

 versely ; superior anal appendages long and black, the lateral sur- 

 faces subcircular in outline, the mesal surfaces emarginate about 

 the middle ; inferiors as long as the superiors, straight, and with 

 a small apical hook directed mesad (Fig. 12, Nos. 3, 4). 



Female. — Color metallic green. 



Head : as in male. 



Thorax: wings pale brown, darker at tips and transparent; 

 stigma present, white (Fig. 12, No. 6) ; antenodal cross-veins 

 23-26. 



Measurements: length, male 43-46, female 41-42 mm.; length 

 of abdomen, male 32-38, female 32-33 mm. ; length of hind wings, 

 male 28-29, female 29-30 mm. ; width of hind wings, male, 9.5-10, 

 female 10 mm. 



Connecticut. — Scotland, 25 July, 1904 (B. H. W.) ; Mount Carmel, 27 

 August, 1904 (P. L. B.) ; Orange, 21 July, 1905 (W. E. B.) ; Branford, 

 28 July, 1905 (H. L. v.), 5 July, 14 August, 1905 (H. W. W.) ; Goshen, 

 6 July, 1919 (M. P. Z.) ; New London, 6-16 June, 1921 (R. H. H.) ; 

 Litchfield, 26 July, 1916 (L. B. W.). 



New England. — April i6-August 2rj. 



Genus Hetaerina Hagen 



The nymphs are similar in structure but much lighter in color 

 than those of Agrion. The median cleft of the mentum does not 

 extend proximad of the articulation of the labial palpi; and the 

 gills are also much lighter in color than those of Agrion. 



Adults of this genus are distinguishable by means of the bright 

 carmine patch at the base of the wings in the male. The cuticle 

 is dark green or bronze, but rarely as dark as the cuticle in the 

 genus Agrion. 



Only one species (americmm) is known from the New England 

 States, but a second (titia) occurs in the Middle West. The latter 

 species, however, is easily distinguished from americana by the 

 brown color at the base of the hind wings of the male and the 



