Octopus Eye - However underwater light has a polarized component which some octopuses can detect. When this light travels through the body of a transparent animal its polarization will be changed and the octopus can see that and capture the prey.
blue ring octopus - Produce a strong Nero Toxin called Tetrodotoxin. this Octopus uses as a defensively. It also has a Toxin that is Harleysville to humans and is used on its prey. This little fellow is found in Tide poles in semi warm climates.