The North American Caddis-Fly Larve 
FAMILY PHRYGANEID-. 
Of the three of four genera of Phryganeide occurring in 
North America, only two genera, Neuronia and Phryganea, have 
been recorded in the eastern part of the United States. Of these 
the genus Phryganea has four species and Neuronia has eight 
species in this region; three of each genus are known in the larval 
and pupal stages. The eggs of only one North American species, 
Phryganea interrupta, are known. 
The larvee of the family are usually among the first aquatic 
insects attracting the attention of students of entomology. Large, 
brightly colored, caterpillar-like insects that jerkily drag their cases 
about in the clear waters, they can not pass unobserved. 
Though the larvee do move about and feed in the daytime, they 
are typically creatures of the night. If one watches them in an 
aquarium he will find that a large part of the day is spent in rest, 
with the front end of the case fastened to some support by a film 
of silk. When night comes, the cases are loosened and the larve 
crawl actively about, greedily feeding upon whatever vegetation 
their abode affords. . 
The immature stages of the Phryganeide are better known than 
those of any other family of American Trichoptera. Our better 
knowledge of them is perhaps due to their conspicuousness and 
the ease with which they can be fed and reared in captivity. Om- 
nivorous plant feeders, and dwellers in ponds or slowly flowing 
streams ; furnished with a great area of gill surface which is con- 
stantly bathed with changing water pumped by the unceasing 
rythmic waves of the body, they thrive in laboratory aquaria. 
The greatest danger that besets the captive larve, when sev- 
eral are confined together, comes at the time of pupation. After 
the earliest have attached their cases and have become inactive, 
they fall easy prey to the ravenous appetites of those still active. 
In nature, however, due to the burrowing habits of the larve be- 
fore their activity ceases, it is probable that they are seldom dis- 
turbed by others of their kind. 
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