THE AUSTRALIAN LUNG-FISH 



381 



like a reptile, and its swimming-bladder is so 

 developed that it does duty as low-class lungs. 

 Its gills are very small and imperfect, and of 

 little use. The top of its skull is quite unlike 

 those of other fishes, and its scales are very large. 

 Its pectoral and ventral fins are very long and 

 leg-like, and are covered with scales everywhere 

 save on the edges, where the fin-rays are situated. 

 One of the most extraordinary features of this 

 strange fish is the possession of large and very 

 remarkable molar teeth, those above being set in 

 the palate (vomer), and evidently designed for 

 the cutting up of vegetable food. Leaving bony 

 anatomy out of consideration, it is quite clear 

 that the living fish which stands nearest to 



Ceratodus is the jumping fish or mud-skipper, 

 of the Malay Peninsula, which hops about on 

 land with surprising independence and agility. 

 Its long pectoral fins are really foot-like in use- 

 fulness. 



Both in the Burnett and Mary Rivers of 

 Queensland, where it lives, and also in captivity, 

 this Lung-Fish frequently rises to the surface of 

 the water to take breath, like a porpoise. 



The allied Mud-Fish (Lepidosi'ren) of the 

 Amazon, and the African Mud-Fish (Protop'- 

 terus) of the River Gambia, have legs that are 

 mere wisps of skin and flesh, and strongly re- 

 semble our Amphiuma, of the Class Amphibia. 

 They are rarely seen alive in captivity. 



