AQUATIC INSECTS IN 
from water [fig. 22]. 
NEW YORK STATE 447 
Miall’s observations of S. lutaria 
quite agree with this, and he further states that the adult 
emerges after _two or three 
weeks. 
Adults. These have already 
been described above. They are 
very awkward fliers and are 
easily caught even without a 
net. This quite agrees with the 
generalized form of the wing 
venation [fig. 23]. In fact, the 
adults when approached, will 
often run rather than attempt 
to fly. It is probable that 
the insect lives in the winged 
form only a few days. All 
specimens taken were found 
to die within three days. The 
dates on which the adults 
have been collected near Ithaca 
range from May 13 to June 
16, through a series of years. 
They are diurnal in _ their 
habits and seem to prefer bright sunshine. 
Fig. 22 Pupa of Sialis infumata x3 
(After Needham) 
I have found them 
most abundantly in their egg-laying places at midday, though 
they also frequent the same places and are active till almost 
dark. 
The short life taken with the fact that the mouth parts o 
the adult are very poorly developed, would indicate that the 
Rs 
Fig. 23 Fore wing of Sialis infumata x4 
adults do not take food. It 
was reported to Dr Hagen and 
to the national museum some 
years ago that the adults of 
S. nevadensis were very 
injurious to grapevine leaves. 
This is the only case of injury 
yet charged to any members 
of the family, and may be a 
false charge. On the other 
hand, the adults, flying near 
the surface of water, serve as an abundant supply of food for 
fishes. 
KEY TO SPECIES OF 
a Body and wings black or blackish 
SIALIS 
b Head black with flat, shining streaks and spots 
yellowish 
