TiLLYARD.—Stone-flies of New Zealand, 199 
For the separate areas of the wing, or wing-spaces, the rule is that they 
should be named from the vein bordering them anteriorly. Thus the costal 
? 
ein 
defined in the preceding paragraph ; in the forewing it is sometimes more 
The anal area is the whole area lying posterior to the cubito-anal furrow, 
and carries on it all the anal veins, which are convex. In the forewing 
vus 
anal fan from the rest of the win in all families of Perlaria except 
the Eustheniidae (fig. 1); in this latter family the outer margin forms a 
single continuous curve. The number of veins on the anal fan, their 
condition, whether branched or simple, and the presence or absence of 
cross-veins between them, are important family characters within the order. 
Ккү то THE FAMILIES OF THE ORDER PERLARIA FOUND WITHIN NEW ZEALAND. 
. Imagines. 
‘Large insects with numerous cross-veins on all parts of the 
wing, including the anal fan, whose margin forms an un- 
broken contour with that of the rest of the hindwing ..  EUSTHENIIDAE. 
insects in 
no cross-veins (rarely one only), and its margin joins the 
margin of the rest of the hindwing in a re-entrant angle or 
2 адеж cord absent; distal cross-veins present . vie 3 
1 Transverse cord present ; no distal cross-veins. ж .. NEMOURIDAE. 
^Forewing with Sc, ending u beyond two-thirds of the wing- 
length from the base, leaving à short pterostigmatic region 
beyond it. Ana th seven or eight ma 
34 sive of 1A ; first branch of 2A a forked vein .. .. AUSTROPERLIDAE, 
Forewing with Sc, ending y Жем between one-half and two- 
thirds of the wing-length from the base, thus leaving a long 
pterostigmatic region beyond it. Anal fan with only six 1 
main veins, including 1A, and none of them fork .. LEPTOPERLIDAE. 
B. Larvae. 
ү ( Larvae with visible gills .. sia e v 2 
1 Larvae without visible gills E - c ne 3 
ills a series of paired latero-vental abdominal appendages on 
segments 1—5 or ie se ғ» T .. JEUSTHENHDAE. 
2 4 Gills a rosette of numerous small filaments arranged around the 
an ix EA Ms M pa .. LEPTOPERLIDAE. 
Larvae of small size and normal shape, with minute cerci 
consisting only of a single segmen ve vs ... NEMOURIDAE. 
3 2 Larvae of moderate size and of long, cylindrical shape, with 
short cerci consisting of a moderate number of short 
segments  .. e. vr a x .. AUSTROPERLIDAE. 
‘ 
Family EUSTHENIIDAE. 
Subfamily STENOPERLINAE. 
Insects of large size, slender build, and of green, yellow, brown, or grey 
coloration. Forewing about five times as long as broad, the costa not 
i basally. Cerci short. Male with short superior appendages and 
short upturned copulatory hook. 
