Vorhies—Studies on the Trichoptera of Wisconsin. 691 
appearance. The whole case now lies close to the stone when 
the opening, which is now ventral, is applied to the surface; 
this opening is entirely closed by a membrane, the outer surface 
of which adheres to the stone. A small transverse slit is left 
open low down in the anterior rounded end. 
Habits and Occurrence. —These larvae are very plentiful in 
Lakes Mendota and Monona, in rather shallow water, where 
there is some Potamogeton. From the rocky promontory at 
Tenney Park, they may usually be taken without the use of a 
boat, by collecting from the stones along the shore. 
The pupal stage lasted 12 days in the laboratory. I have not 
been able to observe the transformation from pupa to adult, but 
have some reason to believe that it takes place in an exceed¬ 
ingly short time. The pupal skins are left floating on the sur¬ 
face of the water. Adults are common in the latter part of 
June, when they may be taken with a trap lantern, or, along 
the lake shore, with a net. 
(PL LIII, Fig. 3. PI. LVII, Figs. 20-22. PI. LVIII, Figs. 
1-7.) 
Leptocerus ancylus nov. sp. 
Imago. —Length of body, 5-6 mm. Expanse, male, 20-21 
mm.; female, 16-17 mm. Antenme, male, 20 mm.; female, 10 
mm. Antennae dark browm, the basal half annulated with snow- 
white on the proximal part of each segment, annulations more 
distinct than in dilutus. Head and thorax brown, with warts 
and pubescence as in dilutus, except the admixed dark hairs are 
brown rather than black. Abdomen green to brown. Legs sil¬ 
very gray, brown coxae, brown spines on the tarsi, the latter 
flecked with brown on the distal ends of the joints. Anterior 
wings brown, with more luteous hair than in the preceding 
species; fringed with brown, a yellowish spot at the arculus, not 
conspicuous. Posterior wings grayish-hyaline, iridescent, with 
sparse gray pubescence, fringed with same. 
In the male the 9th dorsal segment is extended medially, end¬ 
ing in a rounded tip. The superior appendages are plate-like, 
rounded at the extremities, without the long hairs on the bor¬ 
der. Penis cover much as in dilutus, the ring-like thickening 
46—S. & A. 
