252 



PISCES 



The African lung-fishes {Pj-otopterus) feed on worms, crustaceans, 

 frogs and insects. They burrow into the mud, secreting a cocoon of 



Anieniof dorsa/ f/'n ri./f ' 



PectorsJ fin-^ 



Nostri/s, 



'Poster/or donsa/ fin 



?' r^i/fin 



JS'c/e' 



A (Ji// coven' ^ ^^^^'-Pe/v/c fin j^ T 



*- -Ifead A Trunk ^ Ta// -^ 



K. S- FLSM CoMttlNMnv V. 



Fig. 136. Yellow perch indexed. (Courtesy of Amer. Mus. of Nat. Hist.) 



slime, and aestivate during the dry season. A slimy covering en- 

 closes the animal except for a small aperture through which lung 

 breathing is carried on. 



Fig. 137. Australian lung fish, Ceratodus. (Courtesy of Amer. Mus. of Nat. Hist.) 



The South American lungfish {Lepidosiren) is a trifle more 

 terrestrial than Protopterus and lives in a deep burrow in the swamp, 

 laying eggs in the soil. It takes several gulps of air at a time when 

 it comes to the surface of the water. 



