How does ant lion prevent ant from climbing out of pitfall (see Fig. [170])? What is on edge of nearest pitfall? Explain.
Ant lions may be kept in a box half filled with sand and fed on ants. How is the pitfall dug? What part of ant is eaten? How is unused food removed?
How long is it in the larval state? Pupal state? Keep net over box to prevent adult from flying away when it emerges.
Fig. 171.
Fig. 172.—Metamorphosis of house fly (enlarged).
Fig. 173.—Metamorphosis of flea.
