AQUATIO INSECTS IN NEW YORK, STATD , 237 
Nymphs 
a um with no raptorial setae on the mentum 
aa Labium 
within; gills broad, thick, dark colored, 
oval or oblong in shape and obtuse at 
ENDENGM Pep oear ae ates Geek aor ere al onc ete aletat aie cates 
With mental setae; gills thinner, more 
pointed and narrower ![pl.15] 
b Hind angles of the head strongly angulate 
ce Gills widest beyond the middle; body slender; 
head half as lomg as wide. ...... 6.60. 6+: 
ce Gills widest across the middle; body stouter; 
head nearly as long as wide............- 
bb Hind angles of the head rounded 
d Labium with one mental seta (and a rudimen- 
tary Second.one) each side; antennae six- 
jointed; lateral lobe of the labium with 
the distal end above the end hook hardly 
hema tees. cheese tos 0 widie ese ewe 6 er aot 
dd Labium with three to five mental setae each 
side (one may be smaller than the others), 
and end of lateral lobe denticulated dis- 
tinctly; antennae seven-jointed (with the 
possible exception of E. anten- 
natum) 
e Gills more than half as long as the abdo- 
men, lanceolate; third segment of anten- 
nae less than a third longer than the 
second 
f Labium with four to six lateral setae, gen- 
erally with five, and with three (rarely 
four) mental setae each side; gills often 
with a definite color patterm.........+.. 
ff Labium with five or six lateral setae, and 
with four mental setae each side; gills 
generally with no distinct pattern....... 
eé Gills less than half as long as the abdo- 
men, narrower and with a long tapering 
point; third segment of antenna more 
Argia 
Chrom arg rion 
Amphiagrion 
Nehallennia 
Enallagma 
Lsennursa 
than a third longer than the second..... Anomalagrion 
ARGIA 
This is another large genus whose species are nearly all 
American, and whose habitat is chiefly tropical or subtropical. 
In New York State are recorded five species, and a sixth is 
regional and is included in this list. 
Of these six, four have 
been bred, and their nymphs are here described for the first 
time. 
