A DRAINED FISHPOND. 



a further stage, is a six-foot-long fish which 

 inhabits loaded streams, where its gills do 

 not suffice it for proper respiration ; it has 

 therefore altered its swim-bladder into a 

 rudimentary lung, more advanced than the 

 bow-fin's, and full of air-cells, richly supplied 

 with blood-vessels, but consisting still of a 

 single cavity. Nevertheless, even this im- 

 perfect lung enables the mud-fish to stroll 

 away from its native streams at night, and 

 wander at large on dry land by means of 

 fins which are almost legs, and which act 

 like the sprawling limbs of certain southern 

 lizards. In that unnatural environment it 

 browses on green leaves, and otherwise 

 behaves in a most unfishlike manner. 

 Finally, to complete our rough survey, the 

 African lepidosiren makes its home in waters 

 which dry up completely during the hot 

 season ; and it therefore hibernates (or rather, 

 aestivates) for months together in a cocoon 

 of hard mud, where it breathes at its ease 

 by means of true lungs, completely divided 

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