PLECOPTERA NYMPHS OF NORTH AMERICA — 67 
sharp, incurved tooth, and with a second large tooth followed by 
a row of five or six stout hairs. 
Labium: first segment of palpus about half again as long as 
wide, second nearly twice as long as first, third a little shorter 
than second and much more slender; glossae short and rounded ; 
paraglossae large, broadly rounded and extending much beyond 
the glossae. Hypopharynx broadly rounded and beset with many 
short hairs. 
Pronotum much wider than long; angles broadly rounded. 
Middle portion of pronotum yellow bordered by brown and with 
a narrow yellow margin. Meso- and metanotum patterned with 
yellow and brown; wing pads broadly rounded. Legs with a 
_ fringe of hairs on the femora and tibiae; first and second segment 
of tarsus very short, subequal; third concn at least four times 
as long as one and two together. 
Abdomen slightly depressed, alternately banded with yellow 
and brown. Cerci about half as long as the body. 
The gills are long and much branched. There are nine pairs 
in the mature nymphs, located as follows: two smaller pairs at 
the outer base of the prothoracic legs, one large pair attached to 
the lateral margin of the conjunctivae, between the pro- and 
metasternum; two smaller pairs at the outer base of the meta- 
thoracic legs; one large pair attached to the lateral margin of 
the conjunctivae between the meso- and metasterna; one smaller 
pair at the outer base of the metathoracic legs; one large pair 
on the metasternum posterior to the hind legs; and one pair of 
eaudal gills. 
In the immature nymphs, not all of the above gills are found. 
Specimens which measure only 4 to 5 mm. in length may possess 
only four pairs of gills, three pairs thoracic and one pair caudal. 
Neoperla clymene Newman 
(Plate 7, figs. 111-116; plate 19, fig. 195.) 
Length of body up to 13 mm.; antennae up to 6 mm.; cerei 
up to 6 mm. 
General color yellowish with a brown-bordered pronotum, a 
bar across the anterior part of the head, and brown transverse 
bands on the abdominal segments. 
The nymphs of this genus are at once recognized by the fact 
that they possess only two ocelli, which are placed very close to- 
gether. The head is as wide as the pronotum, yellow, with brown 
over entire clypeus, the anterior margin of the labrum brown, 
