Fin rays

• These supporting rays may be bony, cartilaginous, fibrous, or horny
• The movements of the fins are due to the action of the muscles, these movements being possible because of the articulations and often flexibility of these rays.

Types of fin rays

a) soft rays: These are thin, flexible, most often branched, segmented, and always biserial (two lateral components paired on the midline).

b) Hard rays (Spines): Several soft rays united solidity to compose hard rays which are stout, rigid, unsegmented, uniserial, and sometimes sharply pointed.