forms of aquatic insects in their immature stages. 
are printed in italics. 
are not remarkably different from the adults. 
4I 
The wings develop externally 
HasitatT 
GILLs OTHER PECULIARITIES Foop-HABITS 
many, minute, around] .................... rapids mainly carnivorous 
bases of the legs 
@opairsonback. i} ahiateaana aa vada a cokers all waters mainly herbivorous 
3 leaflike caudal gill- 
plates 
internal gill chamber 
at end of body 
wanting 
immense grasping lower 
lip 
immense grasping lower 
lip 
jointed beak for punc- 
turing and sucking 
slow and stagnant 
waters 
slow and stagnant 
waters 
all waters 
carnivorous 
carnivorous 
carnivorous 
of the same species, being more or less wormlike, having wings developed 
mentary, or even wanting (Jarvae proper). 
Rear Enp oF Bopy| OTHER PECULIARITIES HABITAT Foop Hasits 
a pair of fleshy pro-| ..................5. still waters herbivorous 
legs with numerous! 
claws on them 
do., with paired larger} mostly living in port-| all waters mostly herbivorous 
hooks at tip 
a long tapering tail 
paired hooked claws 
variable * 
see next table 
able cases 
head small, often ap- 
parently wanting 
gravelly beds 
all waters 
slow or stagnant waters 
all waters 
carnivorous 
carnivorous 
carnivorous 
see next table 
guished from aquatic larvae of other groups by the absence of true legs. 
Fresuy Lecs, or Pro- 
LEGS 
OTHER PECULIARITIES 
HAaBiItaT 
Foop Hasits 
variable 
wanting 
wanting 
one beneath the mouth 
I in front, 2 at rear 
end of body 
wanting 
wanting 
stout paired beneath 
wanting 
usually 
flat lobed body with 
row of ventral suckers 
swollen thoracic  seg- 
ments 
‘fans’ on head for 
food-gathering 
live mostly in soft 
tubes 
depressed form 
tubercle covered spin- 
dle-shaped body 
shoals 
rocks in falls 
pools (at surface) 
rocks in rapids 
all waters 
still water (at surface) 
beds in pools 
rapids under stones 
shallow pools 
herbivorous mostly 
diatoms, etc. 
herbivorous 
herbivorous 
herbivorous 
herbivorous 
carnivorous 
carnivorous 
