302 DRAGONFLIES OF NORTH AMERICA 
black sinuate line on either side. Thorax (p. 289) with the blue antehumeral 
stripe from two-fifths to nine-tenths as wide as the black middorsal. The black 
humeral stripe of unequal width throughout, the middle third sometimes want- 
ing, seldom forked. A black line on the third lateral suture. Abdomen with 
segment 1 mostly blue. Segment 2 blue with a longitudinal black stripe on each 
side, the posterior end of which is triangularly dilated, and does not reach the 
apex, or this stripe represented only by a black anteapical spot. Segments 3-7 
blue, each with a postbasal streak, and the apical third to fifth black, the post- 
basal streak usually not united with the apical black except on 7 and occasionally 
on 6 also; on 7 the black occupies the entire dorsum except a pale basal ring; 
the postbasal streaks are often absent on 3, and less frequently on 4 or 5; 8-9 
blue unmarked. 
Female.—Differs from the male as follows: Pale brown often replacing the 
blue of the male. Segment 9 as in the male, or, more frequently, with a short, 
black, basal stripe on each side of the dorsum. 
For descriptions and notes regarding southwestern subspecies of 
vivida, see Calvert, 1902. 
64. ARGIALLAGMA Selys 
This genus belongs to the same division of the Coenagrioninaeas does 
Argia and Hyponeura for, as in these two genera, the front row of setae 
on the tibia are all very long, being twice as long as the spaces sepa- 
rating them. It differs from these genera however, by the smaller 
number of these setae (5-7 on the 3rd tibia), in the reduced number of 
the postnodal cross veins with the result that Mb: arises nearest the 5th 
in the fore wing and the 4th in the hind, and in the presence of a ventral 
spine on the apical margin of abdominal segment 8 in the female. 
There is but one known species: 
293. Argiallagma minutum Selys 
Selys ’57, p. 464: Mtk. Cat. p. 52. 
Syn: aduncum Hag. 
Length 26 mm. Expanse 28-33 mm. Fla. 
A rare species of damselfly found in southern bogs and swamps. 
Male.—Colors metallic black and pale yellowish. Head entirely pale beneath 
Labrum pale with the basal half black. Postclypeus black; anteclypeus pale. 
The pale transverse frontal stripe covering the vertical portion of the frons and 
the horizontal portion to the basis of the antennae. Antennae black, except the 
2nd joint which has a broad median ring of pale. Vertex black. Pale postocular 
spots linear and broadly connected with the pale postocellar stripe on the caudo- 
mesal margin of the head, though separated from the pale color of the rear of 
the head. Dorsum of the prothorax metallic black, sides broadly pale. The 
hind margin of the posterior lobe high and convex throughout. Black middorsal 
thoracic stripe very wide touching the humeral suture at its caudal end, re- 
mainder of the humeral suture with a fine brown line separated from the mid- 
