Vorhies—Studies on the Trichoptera of Wisconsin. 687 
those of tlie female: beneath the bases of these processes, the 
male has also a pair of shorter processes or lobes. Mandibles 
longer than the labrum, straight, sharply pointed, slightly ser¬ 
rate within, two short black hairs on the outer side of the base. 
Labrum a little broader than long, a pair of long, black, hooked 
hairs on either side beyond the middle, a shorter black one, not 
hooked, near the latter, and some short colorless ones on the 
anterior portion. 
Case .—The larvae of this species, (and of the genus) build 
.at first a cylindrical case of sand, slightly curved, tapering de¬ 
cidedly in some instances, while in others the diameter is almost 
uniform. The sand cases measure up to 10 mm. long, one of 
the maximum length measuring 2 mm. in width at the anterior 
end, and 1 mm. at the posterior. These are the cases commonly 
found in the autumn. In the spring a quite different case is 
formed, and enough intermediate stages to prove the change, 
■even if the identity of the larva were not established, may be 
easily found. The later case is square in cross-section, formed 
■of thin flat pieces of bark and leaves; the component pieces are 
rectangular, or sometimes slightly hexagonal in form. The case 
is straight and equi-diametric. Length, 10-12 mm. Width, 2 
mm. This case, cut to the proper length to fit the body snugly 
(8.5-10 nun.), and fastened by strong cords of silk at both ends, 
is used for pupation. The anterior and posterior closing mem¬ 
branes are the same, being sieve-like. 
Habits and Occurrence .—These larvae are quite plentiful in 
the streams at Devil’s Lake and Parfrey’s Glen, where they in¬ 
habit the pools. The pupae were abundant at the Glen on June 
1. They could be found only among roots and grasses where 
these hung in the stream, as, for example, in a bit of overhang¬ 
ing sod. I have not taken the imagos in their natural habitat. 
Those reared in the laboratory appeared in the first days of 
June. 
(PI. LIT, Pig. 8. PI. LVII. Pigs. 1-10.) 
