VIII 

 TRICHOPTERA 



Caddisflies 



This is the largest group of aquatic insects. The adults 

 are abundant enough at the waterside, but they are mostly 

 of rather small size and obscure coloration and nocturnal 

 habits, and they are by most people little noticed. The 

 wings and body are covered with hair.* The antennae are 

 long, often very long, and are extended forward when at 

 rest. Both maxillary and labial palpi are well developed, 

 though the biting parts of these organs are not. The wings 

 are extended to rearward, and meet roof-like above the 

 abdomen. The legs are slender. The tarsi are 5-jointed and 

 the tibiae are armed with large spurs — often more than 

 one pair of spurs on each. 



They are quite inoffensive. Their jaws are little developed 

 and they cannot bite. Only by fluttering in people's faces 

 when extremely abundant, do they cause any inconvenience.f 

 They are of tenest seen when gathered about waterside lights 

 at night, or resting motionless on boats and docks by day. 



The young of the caddisflies, called caddisworms, are 

 better known. Their interesting habit of constructing cases 

 in which to dwell, and carrying these cases about on their 



* Hence the name of the order: trix hair, and pteron, wing. 



t It was a small caddisfly of the Niagara River (Hydropsyche chlorotica) 

 that caused the site of the Pan American Exposition in 1892 to be re- 

 located inland, far away from the river site first selected. It was thought 

 that visitors would not like them, even though harmless. 



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