1939] 
Immature Trichoptera 
13 
ters arising from the ends of stalks, somewhat like 
the tentacles of Hydra ; large forms : 
Hydropsy chidse, subfamily Arctopsy china? 
Gula triangular, never reaching hind margin of head, 
the epicranial halves contiguous for some distance; 
gill filaments arising from the side as well as the end 
of the stalk, more comb-like 9 
9. Dorsal surface of head flattened, forming a broad disc, 
enclosed by a strong carina which crosses the frons 
near its apex, setting off a small triangle ; mandibles 
with broad, blunt teeth on whole inner margin, the 
interspaces broad and deep: 
Hydropsy chidse, subfamily Macronematinse 
Dorsal surface of the head flattened, but with no carina 
defining its limits; mandibles with sharp teeth api- 
cally : . Hydropsy chidse, subfamily Hydropsy chinse 
10. Body campodeiform, the abdomen depressed; larvae 
never constructing a movable case though sometimes 
building a fixed shelter 11 
Body eruciform or suberuciform, the head bent down- 
wards at an angle to the rest of the body ; abdomen 
cylindrical, the sutures between the segments usually 
feebly impressed ; gills usually present ; larvae always 
living in a movable, tubular shelter 12 
11. Prolegs very well developed, entirely separate from 
each other; proleg claws long and slender, without 
teeth on convex surface ; accessory claws sometimes 
present at sides of main proleg claws; maxillary 
lobes long and slender : 
Rhyacophilidse, subfamily Rhyacophilinse 
Prolegs short, the basal segments wholly sclerotized 
and fused to the ninth abdominal segment in a nearly 
vertical position ; proleg claws very short, with small 
teeth on the convex side ; maxillary lobes short and 
broad; construction of a fixed shelter in late larval 
life is usual : 
Rhyacophilidse, subfamily Glossosomatinse 
12. Prosternum with a horn or spine projecting down- 
wards between the front coxse 13 
