INSECT ARCHITECTURE. 



whole by adding a broad piece longer than the rest 

 to shade his door-way over-head, so that he may not 

 be seen from above. A more laborious structure is 

 reared by the grub of a beautiful caddis-fly (Pliry- 

 ganea), which weaves together a group of the leaves 

 of aquatic plants into a roundish ball, and in the 

 interior of this forms a cell for its abode. The fol- 

 lowing figure from Roesel will give a more precise 

 notion of this structure than a lengthened description. 



Another of these aquatic architects makes choice 

 of the tiny shells of young fresh-water mussels and 

 snails (Planorbis), to form a moveable grotto, and 

 as these little shells are for the most part inhabited, 

 he keeps the poor animals close prisoners, and drags 



Shell MwtJ of Caddis- ir«rmt. 



