BRITISH INSECTS 



pond or stream where this insect-denizen loves to dwell. 

 There are more than 170 British species. The adult 

 has long, slender antennae and legs, the front wings are 

 more or less covered with hair, and held roof-like when 

 at rest. The hind wings are less leathery, and are held 

 pleated when at rest. Trichoptera means " hairy- 

 winged," from the Greek trichos—hair, and pteron—a 

 wing. The eggs are laid in water, and the larva, soon 

 after hatching, prepares for itself a case, or tube, in which 

 its soft, grub-like body can be protected. Sometimes 

 these cases are made of small pieces of sticks or leaves, 

 at others they are composed of fine grains of sand glued 

 together. Others bear upon them small water-snails 

 in which their owners are also contained. The tube 

 nicely fits the larva, and is just a Uttle longer each end 

 than the creature's own body. The tail end appears to be 

 sealed up, but the front door remains open until such 

 time as the larva is ready to pupate. The reason for 

 this is that the latter is thus able to protrude its head 

 and legs so as to crawl about and procure food. It 

 fastens itself to stones, submerged posts, piles, and other 

 objects. To dislodge one from its habitation requires 

 some force, as it has two strong hooks which enable it 

 to secure a firm grip inside. It pupates within the 

 case, taking the precaution to close the front entrance 

 before this takes place, and when the almost complete 

 creature is ready to emerge, it swims to the surface 

 by means of its two middle legs, which are fashioned 

 like oars. This accomplished, the skin splits down the 

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