648 Wisconsin Academy of Sciences, Arts and Letters. 
4 
gerated. This ease of identification is due to the fact that the 
fish swallows the case as well as the larva. However, the fig¬ 
ures show that nearly 78% of the food as identified was Trichop- 
terous, and if we allow 28% for error from the above causes, we 
still have 50%, enough to prove the larval Trichop ter a an im¬ 
portant source of food for the trout of Hew Zealand. The trout 
examined were caught in the months from September to March 
inclusive. Prof. Forbes (1880) found in studying the food of 
fishes of Illinois that in a few species as much as 15% to 20% 
of the food consisted of the larvae of Trichoptera. 
The lack of descriptions of immature stages of American, 
forms soon forces one who attempts work of any kind on the 
larvae to turn first to systematic work. It is evident that until 
much more of this work shall have been done the solution of 
problems of other kinds will be handicapped. In Wisconsin an 
excellent opportunity for a study of local distribution is afforded 
by the Trichoptera, but one at once finds that it is desirable to 
be able to identify the larvae without being compelled to tedi¬ 
ously rear each one. 
Hearing work, too, is sure to lead to a. much fuller knowledge 
of our present species, and to the discovery of many new ones, 
as our Trichopteran fauna is comparatively poorly known in 
the imago stage. From the time of Walker (1852) (whose de¬ 
scriptions might better never have been written) and Hagen 
(1864, ’73, ’73 (2)) the worker in this group finds a notable 
gap in the systematic literature up to the time of Banks, who 
has described more than 150 of the total of 332 species listed 
in his recent catalog (1907). 
The present paper, then, from stress of circumstances con¬ 
tains principally life-histories and habits. It was at first my 
intention to attempt a study along the line of local distribution, 
but the other work having taken up the major share of atten¬ 
tion, I have no such observations to offer, aside from what may 
be contained in the notes on the habits and occurrence of each 
species. 
Wisconsin, partly by reason of its many lakes and streams, 
affording a great variety of breeding places, and partly on ac¬ 
count of its geographical position, affords excellent opportunities 
