THE NEW YORK AQUARIUM 



The hellbender, the largest American salamander, has 

 well developed lungs and, although a water dweller, comes 

 to the surface to breathe, swallowing air through the mouth 

 and passing it back into the lungs. It has, however, a gill 

 opening on each side of the throat. 



The giant salamander differs from its American relative, 

 the hellbender, in having no gill openings. It lives in small 

 streams of mountain meadows and is used as food by the 

 Japanese. 



The mud puppy breathes with gills like a fish and rarely 

 rises to the surface. It has short but well developed limbs 

 and is a nocturnal animal, hiding in rock crevices or weed 

 masses in the daytime and swimming or creeping about at 

 night to feed on Crustacea, fishes, worms and frogs. 



Other fresh-water fishes on this floor are the small lad- 

 der fish, a rare little fish from the interior rivers of South 

 America, common catfish, chub, sucker, red horse, Missis- 

 sippi catfish and spotted catfish, sunfish, fresh-water killie, 

 white perch and the burbot, a fresh-water representative of 

 the cod family. 



A tank of very interesting little sea horses, the only fish 

 with a prehensile tail, is also exhibited on this floor. The 

 sea horses are difficult to keep in captivity because they 

 feed only on the minute crustaceans infesting the eel grass 

 in which they live. The male of this species hatches the 

 eggs and cares for the young in an abdominal pouch. En- 

 closed in a skeleton of horny segments that permits little 

 lateral flexion, and having only one dorsal fin, the sea horse 



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