LIMNOPHILID&. 
In the habitat where the bottom is of muck the larvz use small 
chips of bark in the structure of their cases, making them as 
nearly the typical form as the nature of the material at hand will 
allow. 
The case of the pupa is like the case of the larva, except that 
there are pebbles of large size grouped around and over the front 
end of the case, giving it a rounded form. The opening at the 
caudal end of the case is covered and rounded with pebbles of 
about the same size as those of the larva’s case. At each end the 
case is perforated through the silk lining between the pebbles, by 
from one to six round holes, figure 97. 
The pup cases from the mucky situation had many small 
molluscs fastened to the cepahlic end. 
HALESUS GUTTIFER. 
Hasits.—Larve are common in Michigan Streams below the 
swamp, and have been taken in Spencer Lake. It is probably a 
common species in many of our ponds and slow-moving streams. 
In habits the larva does not seem to differ from Pycnopsyche 
scabripennis, but it has not been so well studied. 
Before pupation the larve attach the cephalic end of the case 
to the under-side of a submerged log, or within some crevice of 
wood or bark. 
Foop or LarvA.—Fine raspings of decomposed wood seem to 
be the only food of the larve. 
PERIoD OF EMERGING.—Specimens in captivity emerged dur- 
ing August and September. Wild specimens have been taken on 
the wing as late as November. 
DEscriPTION oF Larva.—No constant characters have been 
found that will distinguish between the larve of Pycnopsyche 
scabripennis and Halesus guttifer, except the size and form of the 
spacing humps. In H. guttifer the dorsal and lateral humps are 
well developed; the dorsal hump is cone-like, terminating in an 
acute nipple-like process. 
The description of other parts of the larve of Pycnopsyche 
scabripennis will apply equally well to Halesus guttifer. 
DESCRIPTION OF THE CasE.—Halesus guttifer makes ballast- 
stick cases and irregular prepupal cases, which are not distinguish- 
67 
