Vorhies—Studies on the Trichoptera of Wisconsin. 665 
III, 3. 4. 3-4 + 12-15. 3-4. 3-4, VII. The lateral line 
begins on the posterior part of the 5th segment and forms a loop 
beneath the 8th. The gills seem to be as in the larva, perhaps 
averaging fewer branches in a place. The last segment ends 
in a pair of lobes, each bearing a slender, slightly upturned 
process, with rounded ends turning outward, terminated by two 
black hairs. Labrum broader than long; a group of live long 
hooked hairs on either side in front, and two smaller ones, not 
hooked, on each side posteriorly. Mandibles straight, finely 
toothed within. 
Case. —Length, 20-25 mm. Width, inside, 4.5-5 mm. The 
external measurement is so variable that the internal diameter 
is given. It is a straight tube, with a small central opening at 
the posterior end. The case is extremely variable as to the 
kind of material of which it is composed, the larva using bits 
of wood, pieces of plant stem and leaves, seeds, or shells, though 
I have found none of the latter kind in Wisconsin. These ma¬ 
terials are built up very irregularly, and the case often has a 
very bulky appearance. The cases in the streams at Lake 
Wingra show a seasonal variation, the cases of the younger 
larvae, in the autumn, being often nearly or quite as broad as 
they are long, composed of pieces of leaves placed with their 
edges transverse to the long axis of the tube. The anterior view 
of such a case presents the appearance of a very thick-walled 
tube with a small lumen. The pupal case is closed with a sieve¬ 
like membrane. This case is mentioned more frequently than 
any other in the literature. 
Habits and Occurrence. —These larvae are very common in 
the small streams, where not too swift, and are probably more 
frequently encountered by the amateur than any other. They 
are quite plentiful among the watercress in the streams about 
Lake Wingra, and are also found in Merrills Springs and in 
the stream at Devil’s Lake, as well as in the lower portion of 
the stream from Parfrey’s Glen. At the end of July very small 
larvae may be collected by using care, though they are not large 
enough to be conspicuous until late autumn and winter. They 
may be kept in the laboratory rather easily, where they will 
feed on Elodea, N. officinale , or, vegetable food failing, on dead 
