PRESERVING 



197 



3. Cut and fit sods in flower pots for a few of the live 

 cages shown on page 200. 



4. A single caddisworm net-spinning trough will be 

 needed. The making of it is a small job for the manual 

 training shop.* 



F ig. 70. — A trough for net spinning caddis worms, in which "made to order" food-catching nets 



are easily obtained. 



* The materials needed are: (a) a piece of wire cloth 2" x 3"; (&) two 

 pieces of flooring or other stuff, grooved on one edge and two feet long; 

 (c) two strips of equal length for the sides; and (d) a short cross strip for 

 the intake end. 



Make it as follows: Nail the two grooved strips together to form the 

 bottom. Saw a cross-groove near one end to receive the screen. Place the 

 screen in this groove, bending the ends flat against the sides of the bottom 

 pieces. Nail on the two side pieces so that they will stand an inch higher 

 than the bottom. Nail the short strip across the intake end (the end opposite 

 the screen), in position, projecting both above and ]below the trough; 

 below, far enough to give a slant to the trough of about an inch per running 

 foot. If the bottom be painted black inside and dried before use, the nets 

 made in this trough will show up better. 



