332 DRAGONFLIES OF NORTH AMERICA 
325. Enallagma concisum Williamson 
Wmen. ’22, p. 117. 
Length 31 mm. Expanse 34 mm. Fla. 
This species, but recently described, is generally found resting on the vegeta- 
tion of ponds where the water is about waist deep. It is one of the species belong- 
ing to the orange-black group. Male. Postclypeus orange, a transverse black 
stripe at the base and on either side; at mid-length a small black or brown de- 
pression. The pale transverse frontal band is wide reaching the level of the 
median ocellus on either side, but the latter is bordered in front with a small 
pale area of varying size and an anterior projecting quadrangle of black, the latter 
often unsymmetrical. Pale postocular spots linear, cuneiform, widely separated 
by black from the pale color of the rear of the head, but joined with each other 
by way of the pale postocellar stripe on the caudo-mesal margin of the head. 
Vertex black with a pair of pale spots near the lateral ocelli. Prothorax shining 
greenish-black, front and hind lobes broadly edged with orange; sides of the 
middle lobe pale orange, dorsum of middle lobe with a round orange spot, of 
varying size, on either side, and with a median orange twin spot of varying size 
present or wanting. Thorax with black middorsal stripe about .67 mm. wide, 
pale antehumeral stripe about .33 mm. wide, and black humeral stripe about 
.43 mm. wide. Third lateral suture with a black stripe for its entire length, 
widening above from a narrow line at its lower end. Abdomen with the segments 
dark except 9 which is orange on the sides and apical membranous rings of 
orange. Superior appendages not bifid and longer than 10. 
326. Enallagma ebrium Hagen 
Hag. ’61, p. 89: Mtk. Cat. p. 59: Garm. 717, p. 540: and ’27, p. 71. 
Length 29 mm. Expanse 38-40 mm. N.S. to Md. and Wash. 
A common species that often leaves the lakes to fly in the woods and fields. 
Colors, blue and black. Male. Head below pale. Face blue. Postclypeus black. 
Pale transverse frontal band reaching the basis of the antennae. Vertex, antennae 
and the remainder of the frons black. Postocular spots large, oval and isolated. 
Prothorax black on the dorsum with the usual pale markings, i.e., a transverse 
pale stripe on the anterior lobe, two lateral spots on the middle lobe, and the 
posterior margin of the posterior lobe. Thorax with the middorsal dark stripe 
and the antehumeral pale stripe of about equal width, both being wider than 
the dark humeral stripe. Third lateral suture with a black basal spot. Abdomen 
blue, black as follows: a basal semi-ring on 1; apical spot and ring on 2; apical 
third of 3-5; apical half to two-thirds of 6, almost all of 7; all the dorsum of 10. 
8-9 entirely blue. Superior appendages black, bifid, the notch formed being 
circular. Upper and lower arms of equal length and width. No tubercle. 
Female: Color, blue or yellow, and black. Head and thorax similar to the 
male. Abdomen with broad dark dorsal stripes on 2-10, the stripes contracted 
to the meson on the basis of segments 3-7, and widened subapically on segments 
2-7. First segment pale with black basal spot. 
327. Enallagma exsulans Hagen 
Hag. ’61, p. 82: Mtk. Cat. p. 59: Garm. ’17, p. 542: and ’27, p. 80: Byers 
27, p. 387. 
Length 32-53 mm. Expanse 42-44 mm. Eeastern U. S. west to Tex. 
