324 DRAGONFLIES OF NORTH AMERICA 
base of the sclerite, 3-6 with narrow dorsal black lines widened near the apices, 
7 with a similar but broader dorsal line, caudal half of 8 and all of 9-10 black. 
309. Enallagma clausum Morse 
Morse ’95, p. 209: Mtk. Cat. p. 56: Kndy. ’15, p. 299 (Annals E. S. A.): Kndy. 
"17. p: O19! 
Length 31-33 mm. Expanse 42 mm. Kan., Nev. and Wash. 
A western intermountain species, an inhabitant of the desert and seemingly 
enjoys its life in the alkaline ponds of this barren region. Color, blue and black. 
Male. Head pale beneath. Postclypeus with a wide black basal spot. Pale post- 
ocular spots wide, triangular, and entirely surrounded by the black of the head. 
Prothorax black with the anterior lobe transversely lineate with pale, middle 
lobe with or without pale lateral spots, posterior lobe margined with pale. 
Thorax with the mid-carina black or lineate with pale; middorsal black stripe 
rather narrow; dark humeral stripe very narrow, widest at and more or less 
broken at the suture; pale antehumeral stripe wide, at least two-thirds as wide 
as the middorsal dark stripe. Abdomen blue, black as follows: a basal spot 
on 1; an apical spot and ring on 2; apical two-fifths to two-thirds of 3-5; with a 
longitudinal stripe narrowed submarginally; apical two-thirds of 6; almost all 
of 7; and all the dorsum of 10. 8-9 entirely blue. Superior appendages not bifid, 
shorter than 10, pointed and recurved at the tip, somewhat like EZ. recurvatumi. 
Female, similar to the male, except the apical black spots on the abdominal 
segments 3-7 occupy the greater part of the dorsum, however, they do not reach 
the basal margins of the segments. Segment 8 entirely blue. Dorsum of 9-10 
black. 
310. Enallagma cyathigerum Charpentier 
Charp. ’40, p. 163: Mtk. Cat. p. 57: Garm. 717, p. 534 and ’27, p. 70: Smn. ’27, 
p. 14.: Lucas, W. J., The Entomologist, 34:69, pl. 2, S. 5, 1900. 
Syn: annexum Hag., robustum Selys. 
Length 31-32 mm. Expanse 44 mm. North America 
This species enjoys the widest distribution of any of the New World Enal- 
lagma, being found the world over, except in the tropics. Color blue and black. 
Male. Head buff beneath. Postclypeus black with wide blue lateral margins, 
and blue transverse area above on the frons. Vertex, antennae and the remainder 
of the frons black. Postocular spots large, pear shaped and separate. Prothorax 
black with the most of the anterior lobe, 2 spots on the median lobe, the caudal 
margin of the posterior lobe, and the sides blue. A narrow humeral black stripe, 
a wide antehumeral blue, and middorsal black, stripe. A black spot at the base 
of the third lateral suture. Remainder of the thorax blue. Mb) arising between 
the 4th and 5th postnodal cross vein in the fore wings, the 3rd and 4th in the 
hind. Abdomen blue with the following black: a basal spot on 1; a subapical 
dorsal spot and apical ring on 2; apical spots and rings on 3-5; caudal half of 6, 
four-fifths of 7, and all of the dorsum of 10. Superior appendages black, short, 
bent downward with apices acute, not blunt as in boreale. 
Female like the male, blue generally replaced by yellow. Abdomen with 
broad longitudinal stripes on the 2nd segment, those on 3-7 narrower and ex- 
panded near the caudal margin, that on 8 reduced near the front margin. 
