forms of aqttatic insects in their immature stages, 



are printed in italics. 



are not remarkably different from the adtilts. The wings develop externally 



Gills 



many, minute, around 



bases of the legs 

 7 pairs on back 

 3 leaf like caudial gill- 

 plates 

 internal gill chamber 



at end of body- 

 wanting 



Other Peculiarities 



immense grasping lower 

 lip 



immense grasping lower 

 lip 



jointed beak for punc- 

 turing and sucking 



Habitat 



rapids 



all waters 



slow and stagnant 



slow and stagnant 



all waters 



Food-habits 

 mainly carnivorous 



mainly herbivorous 

 carnivorous 



carnivorous 



carnivorous 



of the same species, being more or less worm-like, having wings developed 

 mentary, or even wanting {larvae proper). 



Rear End of Body 



L a pair of fleshy pro- 

 legs with numerous 

 claws on them 



do., with paired larger 



hooks at tip 

 a long tapering tail 



paired hooked claws 



variable 



see next table 



Other Peculiarities 



mostly living in port- 

 able cases 



head small often ap- 

 parently wanting 



Habitat 



still waters 



all waters 

 gravelly beds 

 all waters 



slow or stagnant 

 all waters 



Food Habits 



herbivorous 



mostly herbivorous 



carnivorous 



carnivorous 



carnivorous 

 see next table 



guished from aquatic larvae of other groups by the absence of true legs. 



Fleshy Legs, or Pro- 

 legs 



variable 



wanting 



wanting 



one beneath the mouth 



/ in front 2 at rear 



end of body 

 wanting 

 wanting 



stout paired beneath 



wanting 



usually wanting 



Other Peculiarities 



Habitat 



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 



Food Habits 



herbivorous mostly 



diatoms, etc. 



herbivorous 



herbivorous 



herbivorous 



herbivorous 

 carnivorous 



carnivorous 



