& 
NORTH AMERICAN CADDIS-FLY LARVZE. 
lar hemi-ellipsoid, measuring 10 mm. wide by 15 mm. long.” In 
our collection a single specimen in the prepupal state is inclosed 
in a puparium-like sheet of silk, like that made by R. fuscula. 
SUB-FAMILY GLOSSOSOMATIN&. 
DeEscrIPTION oF LArva.—The head is rounded, not long and 
flattened. The abdomen is round in cross-section, with normal 
inter-segmental constrictions. The prolegs are short and extend 
at right angles to the long axis of the body; their claws are weak. 
The maxillary lobes are short and broad. 
GLOSSOSOMATIN A. 
A. Meso- and meta-notum each with a pair of chitinous plates.— 
Agapetus. 
A.A. Meso- and meta-notum entirely soft—Glossosoma. 
GLOSSOSOMA AMERICANUM. 
LarvaL Hapitat.—The larve are found in all swift waters of 
the region, but reach their greatest abundance in the riffles of the 
upland streams. In the parts of streams with stony bottoms in the 
McLean and Freeville swamps the larve occur in extraordinary 
abundance, their cases completely covering the sides of nearly 
all submerged stones. 
LarvaL Hasrts.—From the time of hatching until the pre- 
pupal stage the larve live singly on the stones of the stream’s 
bottom. Before pupating they congregate in dense colonies on 
the sides and bottom of stones, with their cases placed edge to 
edge—sometimes one on top of another. It is during this prepupal 
stage that the larve are most often encountered. 
Foop oF Larva:.—Stomachs of a large number of specimens 
were examined. All contained a light-colored material, the cellu- 
lar nature of which could not be determined. 
PrEPUPAL Hasits.—In the prepupal state the larve develop 
a gregarious habit—large numbers congregating in small areas. 
At this time the floor of the case is cut away and the entire rim 
of the cup-like roof is securely glued to some solid support. Under 
this cover the puparium-like cover is spun around the larva. 
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