Octopuses have 2 eyes and 4 pairs of arms and are bilaterally symmetric. An octopus has a hard beak, with its mouth at the center point of the arms. Octopus lack an internal or external skeleton allowing them to squeeze through tight places. Octopuses are among the most intelligent and behaviorally flexible of all invertebrates. Blue Ring Octopus
Cuttlefish belong to the class Cephalopoda (which also includes squid, octopuses, and nautiluses). Despite their name, cuttlefish are not fish but molluscs. Cuttlefish eyes are among the most developed in the animal kingdom. They are sometimes referred to as the "chameleon of the sea" because of their remarkable ability to rapidly alter their skin color at will.