102 
NEUROPTERA. 
pale colouring of rear of head. Abdomen chiefly yellowish or 
reddish. Females with the genital valves reaching farther beyond 
the terminal abdominal appendages than the latter are long. 
Superior appendages of the males elbowed and bent down almost at 
aright angle in their apical half . . . . . Loe 
CCCCC. Inferior sector of the triangle arising at least as far in : front of 
the submedian cross-vein as the latter is long. No pale postocular 
spots on a dark ground. Abdomen chiefly red. Females spined as 
above, their genital valves barely reaching beyond the terminal 
abdominal appendages. Superior appendages of the. males not as 
in the preceding genus . . ...... oe 
2. Nodal sector on the hind wings arising at or near to the third postcubital 
segment8 ... . . . . . 
DD. Abdomen chiefly of some other colour than red. Pterostigmata of 
front and hind wings of the males dissimilar in colour, size, or both. 
Tenth segment of the abdomen of the males with a bifid dorsal 
process f. 
or still nearer to the base *. 
D. Abdomen chiefly red. Pterostigmata of front and hind wings similar 
in both sexes, and with the costal side longer than the proximal, the 
anterior distal angle being very acute. Tenth segment of the abdo- 
men of the males with no bifid dorsal process. Females spined on 
. [AmpHiacrionf. | 
E, Pterostigma of front wings of the males touching the costa. Females 
with an external black stripe or line (sometimes interrupted) on the 
second and third tibie$} . . . . . 4. soe. 
EE. Pterostigma of front wings of the males not ; touching the costa. 
Females with no external black stripe on the second and third 
femora . . ‘ oe ew 
$ II. Arculus at least as far beyond the second antecubital as the upper limb of 
the arculus is long. 
Pterostigma and inferior sector of the triangle as above stated for Enallagma. 
Nodal sector, and tenth segment of the abdomen of the males, as above 
for Ischnura. Superior sector of the triangle on all the wings ending in 
front of the level of origin of the ultra-nodal sector . . ..... 
LEProBasis. 
[AmpHracRion. | 
IscHNURA. 
ANOMALAGRION. 
CERATURA. 
* Exceptions are Ischnura erratica and I. cervula of the Western United States and J. inarmata, Calvert, 
of Kashmir. 
Enallagma basidens also falls here, but in all other respects is an Enallagma; the male does 
not agree with the subdivisions of 2 given above, but the female might be supposed to be an Anomalagrion, 
from which it differs in having the costal side of the pterostigma on the front wings much longer than 
the proximal side (the two are subequal in Anomalagrion females) and the greater part of segments 9-10 
blue. 
+t Amphiagrion occupies an intermediate position between sections 1 and 2 of this Key, as twenty-six 
individuals give nearly 50 per cent. for each section. 
t Not bifid in Ischnura kellicotti, Williamson, of the Eastern United States, 
§ Absent in orange females of I. kellicott. 
