430 



THE INSECT WORLD. 



(Fig. 413), resembling a large gnat, furnished with four wings, and 

 Boreus hyemalis (Fig. 414), of a brilliant black, met with in Sweden 

 and in the elevated parts of the Alps, jumping about on the snow in 

 considerable troops are representatives. The latter has been found 

 in England. 



The Phryganida, or Caddis Flies, are known by their larvae, of 



Fig. 4i6.--Phryganea i-horabica, 

 in repose. 



Fig. 415. Larva of Phryganea rhombica. 



Fig. 417. Phryganea rhombica. 



which anglers make great use. Reaumur classed them as aquatic 

 moths. The soft and delicate body of the larvae is protected by a 

 case, to which they cling by two hooks, placed at the extremity of 

 their abdomen. They are called by different names in allusion to 

 their habits ; as, for instance, case worms, from their living in a case 

 covered with little bits of wood or sand, which they draw after them 

 as they go. Their scientific name, Phryganea, signifies fagot.* The 



* From <f>pvyavtov, a stick. 



