The Bony Fishes (Class Osteichthyes) include most fish.
They are cold-blooded vertebrates and breathe through a pair of gills. They are covered with tough, protective scales and have pairs of fins for swimming. Most are flattened from side to side and have an organ called a swimbladder that helps keep them afloat.
ABOUT FISH (Osteichthyes - Bony Fish)