rSbte?^^. 



Fig. 5-1. The African lungfish (Protopterus) undergoes aestivation during periods of drought when the waters disap- 

 pear from its normal habitat. If placed in a container filled with mud it will form its capsule and remam dor- 

 mant for many months in this condition. Pictured here is such a fish being releosed from a can of mud. When 

 placed in water the animal immediately breathes by means of its gills like any other fish. 



