ENALLAGMA 
315 
Group B: Superior appendages bifid; the inferior arm as long or 
longer than the superior. 
Group C: Superior appendages bifid, the inferior arm never as long 
as the superior. 
Group D: Superior appendages as long as, or longer than, the 10th 
abdominal segment. 
Not bifid. Color black with yellow or orange 
markings. Abdominal segment 2 with the black of the dorsum reaching 
from the base to the apex. 
The species may be arranged under these groups as follows: 
aA, 
cyathigerum 
clausum 
divagans 
hageni 
recurvatum 
geminatum 
piscinarium 
boreale 
durum 
minusculum 
laterale 
B. 
ebrium 
exsulans 
weewa 
antennatum 
pallidum 
doubledayi 
carunculatum 
civile 
GC 
anna 
prevarum 
culicinorum 
eiseni 
basidens 
semicirculare 
coecum 
cardenium 
aspersum 
travatum 
KEY TO THE SPECIES 
1. Males 
D. 
cultellatum 
laurenti 
vesperum 
pollutum 
signatum 
sulcatum 
concisum 
pictum 
dubium 
1 Superior abdominal appendages not bifid, the distal margin at 
most only slightly indented giving the appendage a bilobed ap- 
pearence (pollutum, durum, divagans and minusculum)....... 2; 
Superior appendages bifid, consisting of two distinct parts nar- 
rowly joined near the base. There may or may not be a clear 
yellowish tubercle between the arms in the notch of the fork. .21 
2 Superior abdominal appendages small, greatest length less than 
that of the 10th segment. Dorsum of abdominal segment 2 blue 
with a black dorsal spot or spots of varying size, but never cover- 
ing the entire dorsum from base to apex of the segment (except 
@eagans). Color blue and black. «0. .::060.4ku4 a See 3. 
