14 Psyche [March 
No such prosternal horn 15 
13. Body suberuciform ; lateral gills on segments 2 to 7 
usually pubescent with black hairs ; mesonotum gen- 
erally soft like metanotum, rarely with two small 
sclerotized plates ; abdominal constrictions well 
marked : Phryganeidx 
Body eruciform ; lateral gills on segments 2 to 7 never 
pubescent with black hairs; mesonotum generally 
entirely sclerotized, sometimes only with small 
plates, rarely completely soft 14 
14. Mesonotum entirely sclerotized ; metanotum with three 
pairs of plates ; mesothoracic legs stouter and longer 
than hind legs : Limnephilidse 
Mesonotum not entirely sclerotized ; metanotum usually 
entirely soft ; middle legs not longer than hind legs : 
A f ew S ericostomatidx ( Goer inae & Lepidostomatinae ) 
15. Femora of middle and hind legs divided into a shorter 
basal and a longer apical piece; right mandibles 
without inner bristles ; no accessory bristles on back 
of mandibles: 16 
Femora not divided 17 
16. Lateral line well developed 17 
Lateral line little developed or absent : Leptoceridse 
17. Lateral line well developed, the 8th segment never with 
only sclerotized points representing the line ; labrum 
with a transverse row of many stout bristles before 
the middle, or if lacking these, then much longer 
than broad : Odontoceridx 
Lateral line very faint, incomplete or absent, its place 
sometimes occupied on some segments by sclerotized 
points; labrum neither with a transverse row of 
bristles nor longer than broad 18 
18. Antennae rudimentary; pronotum sclerotized, meso- 
notum never more than partially sclerotized : 
S erico stoma tidx 
Antennae large, the basal segment broad, 2nd more 
slender and tipped with a fine bristle ; pro- and meso- 
notum both sclerotized 19 
