NORTH AMERICAN CADDIS-FLY LARVE. 
Abdomen.—The distribution of gills is indicated in figure tro. 
DESCRIPTION OF THE Pupa.—Length, 20—25 mm. The 
mouth parts are weakly chitinized. The labrum is rectangular, 
with rounded corners, about one and a half times as long as wide 
(figure 11). The mandibles (figure 13) are a little longer than 
wide; a broad lobe on the inner corner of the front margin is 
without sete; a smaller, somewhat finger-like lobe on the outer 
corner bears a pair of long sete on its tip. 
The lateral fringe commences on the cephalic margin of the 
fifth abdominal segment and loops under the caudal margin of the 
eighth segment. The last abdominal segment is deeply notched, 
as shown in figure 17; the sides of the notch are flat and disc-like 
on their dorsal surface. The shield on the dorsal surface of the 
first abdominal segment is finely striated with transverse marks, 
as shown in figure 15. The chitinous plates of the succeeding seg- 
ments are shown in the same figure. 
NEURONIA STYGIPES. 
Hasitat.—The only locality record for the immature stages 
of this species is a short area near the headwaters of Argus Brook, 
in the McLean bog. In this region the larve are not uncommon. 
LarvaL Hasits.—The larve wander actively about through 
the trash of the stream’s bottom until the middle or latter part of 
April, when they burrow into the soil or into dead wood for pupa- 
tion. 
PERIOD OF EMERGING.—The habits of the species when emerg- 
ing are like those of NV. postica. In captivity emergence took place 
during the last two weeks of May. During the same period adults 
were common along the stream where the larve were found. 
The adults were seen only close to the stream from which they 
emerged. Here they flew about with slow, jerky flight close to the 
low vegetation beneath the dense alder thicket, or skimmed the 
surface of the small stream. When resting they sought the shelter 
of low weeds or grass. 
Due to their habit of flying during the light of day, and of re- 
maining close to the borders of the stream, the adults of this species 
are more readily seen than are those of other species of the genus, 
which are nocturnal and wide wanderers. 
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