214 DRAGONFLIES OF NORTH AMERICA 
backward; smaller paired pale streaks occur within and without the ‘‘V’s” on 
these same segments. Pleural margins of segments strongly serrate, the posterior 
lateral angles very prominent. Segments 6-9 strongly carinate on middorsal line. 
Appendages brown. 
40. ERYTHRODIPLAX Brauer 
These are slender dragonflies of obscure brownish coloration tending 
to become bluish pruinose with age. The face and frons take on metal- 
lic colors above; the thorax, more or less zebra striped in the beginning, 
becomes wholly obscure. The abdomen is but little swollen at the base. 
The wings are hyaline with only basal flavescent touches. The base 
of vein A; is situated just a little beyond the anal crossing. 
The nymphs are rather thick set and dark colored with no dorsal 
hooks and with rather sharp, lateral spines. They are known for three 
of our four species. 
The Known Nymphs 


Species Length Lat. Set. Ment. Set. Described by 
berenice 14 9-10 10-11 Calv. ’04, p. 174 
minuscula 12 8 12 Ndm. ’04 p. 709 
umbrata 18 10-11 13-14 Calv. ’28, p. 25 

This genus is mainly tropical American. One species ranges far up 
the Atlantic Coast; three others just enter our borders. 
KEY TO THE SPECIES* 
Adults 
1 Radial planate subtends two rows of cells................... 2. 
Radial planate’subtends. one cellrow<..;... = 4-3-0) ce: eee 3. 
2 Median planate subtends two rows of cells....... funerea, p. 215 
Median planate subtends one cell row.......... umbrata, p. 215 
8) \Eexpanse/less than 45 mms) 1. Se eek minuscula, p. 215 
Hxpanse more than, 50)miiy fy. esere. Psion a berenice, p. 215 
* This key does not include the EZ. (Nannophya) maculosa of Hagen (’61, 
p. 187) doubtfully recorded from Georgia; a little species (expanse 33 mm.) 
with a big round, blackish spot covering the base of the hind wing, enveloping 
the triangle and nearly all the anal loop. In the fore wing the point of the triangle 
inclines outward, and the subtriangle is divided by a single cross vein (see Ris: 
de Selys Coll., pp. 526 and 1160). 
