1939] 
Immature Trichoptera 
15 
19. Distal spurs of fore and middle tibiae not on promi- 
nences; hind legs with normal claws; cases curved 
tubes, never broad : Ber seiche 
Distal spurs of fore and middle tibiae on prominences; 
claws of hind legs abnormal ; cases of sand, broadly 
shield-shaped like a turtle shell, except those of very 
young larvae which have straight sand tubes, often 
with bits of mollusk shells: Molannidse 
Key to North American Caddis Pupae 
1. Pupae very small (not more than 5 mm. long, usually 
less than 3.5 mm.), with very short thick antennae; 
maxillary palpi 5-segmented in both sexes; cases 
mostly of silk only or of silk covered with very fine 
sand, the cases flat or thickest in the middle, usually 
attached at each end by circular discs of silk : 
Hydroptilidse 
Pupae usually larger, the antennae nearly as long as the 
body, not especially thickened ; maxillary palpi some- 
times 3- or 4-segmented in the male ; cases never as 
above 2 
2. Lacking both ocelli and a complete tubular case 3 
Either ocelli or a complete tubular case or both present 
5 
3. Gills absent: 
Psychomyiidse, subfamily Psychomyiinse 
Gills present 4 
4. Spurs 3-4-4 ; anal processes large, blunt, not long ; cases 
made of pieces of leaves or small sand grains, the 
ventral side of silk only (in Phylocentropus the case 
is a long, branched tube of sand with only a turret 
projecting; in Neureclipsis the case is a trumpet- 
shaped net) ; 
Psychomyiidse , subfamily Polycentropodinse 
Spurs 2-4-4 or fore tibiae with one or no spur; anal 
processes long and heavily sclerotized, with many 
bristles: Hydropsy chidse 
5. Case complete, the pupa never in an inner silken 
cocoon ; gills often present ; anal processes often long, 
