The below mentioned article provides biology notes on Class Osteichthyes. 1. The endoskeleton is cartilaginous in the embryonic stage, but in the adult forms more or less it is replaced by bones. Thus they have bony endoskeleton. They are ectothermic (cold blooded). There are about 25,000 species of bony fishes. 2. Caudal fin usually homocercal […]