54 ELEMENTARY LESSONS ON INSECTS 



LESSON 4 

 Dragonflies 



WORK PROGRAM 



1. Collect adult dragonflies and damselflies by the water- 

 side: hot sunshiny days will be best for this. 



2. Collect cast nymphal skins of the same. Most of them 

 will be found within a foot of the edge of the water, sticking 

 to plant stems, posts, etc. 



3. Collect dragonfly and damselfly nymphs from still 

 water: a sieve net will get them best; — the climbing nymphs 

 by sweeping the submerged water weeds; the bottom 

 sprawlers by scraping them up with the bottom sediment; 

 the burrowers, by sifting them out of the mud and sand. 



4. Arrange water jars or aquaria for keeping alive a stock 

 of the nymphs for class use. Keep the largest apart, where 

 they cannot eat the little ones. 



5. If full grown nymphs are found, ready for trans- 

 formation (as shown by the length and darkening color of 

 the wing pads on the back), put them in a wire cloth rearing 

 cage (see p. 199), half immerse it in a pail or tank of water 

 and leave them to transform. 



6. Gather mosquito "wrigglers" or other small insects 

 for food for the dragonfly nymphs. 



7. If dried specimens are to be used in the laboratory, 

 give them over-night treatment in a relaxing jar (see p. 186). 



8. Mount a few showy specimens for exhibition, using a 

 spreading-board (see p. 188). 



