lo PLATE CCXX. 



rally form a fort of covering, or tube, for their defencelefs bodies. 

 It is open only at one end, at which its head and fore legs are pro- 

 truded, to take its prey. Some fpecies form thefe coverings of 

 •weeds and fmall fhells, gravel, fand, &c. That of our prefent 

 fpecies, is compofed of little pieces of the ftalks of grafs, cut into 

 an even form, and laid tranfverfely on each other. It attaches this 

 tube to the roots of fome aquatic plants, and undergoes its transfor- 

 mations in it. In the annexed plate, we have reprefented the larva 

 taken from the tube, and the pupa having the tube opened to exhibit 

 its fituation therein. 



The Fly is very common about ponds, rivers, and marihy places. 



PLATE 



