FISH OUT OF WATEK 309 



Scientific interest and filial piety ought alike to secure our 

 attention for the African mud-fish. It lives its amphi- 

 bious life among the rice-fields on the Nile, the Zambesi, 

 and the Gambia, and is so greatly given to a terrestrial 

 existence that its swim-bladder has become porous and 

 cellular, so as to be modified into a pair of true and 

 serviceable lungs. In fact, the lungs themselves in all the 

 higher animals are merely the swim-bladders of fish, 

 slightly altered so as to perform a new but closely alhed 

 office. The mud-fish is common enough in all the larger 

 English aquariums, owing to a convenient habit in which 

 it indulges, and which permits it to be readily conveyed to 

 all parts of the globe on the same principle as the vans for 

 furniture. When the dry season conies on and the rice- 

 fields are reduced to banks of baking mud, the mud-fish 

 retire to the bottom of their pools, where they form for 

 themselves a sort of cocoon of hardened clay, lined with 

 mucus, and with a hole at each end to admit the air ; and 

 in this snug retreat they remain torpid till the return of 

 wet weather. As the fish usually reach a length of three 

 or four feet, the cocoons are of course by no means easy to 

 transport entire. Nevertheless the natives manage to dig 

 them up whole, fish and all ; and if the capsules are not 

 broken, the unconscious inmates can be sent across by 

 steamer to Europe with perfect safety. Their astonishment 

 when they finally wake up after their long slumber, and find 

 themselves inspecting the British public, as introduced to 

 them by Mr. Farini, through a sheet of plate-glass, must 

 be profound and interesting. 



In England itself, on the other hand, we have at 

 least one kind of fish which exemplifies the opposite or 

 migratory solution of the dry pond problem, and that is 

 our familiar friend the common eel. The ways of eels are 

 indeed mysterious, for nobody has ever yet succeeded in 



