Barreleye This unusual fish might be the most bizarre creature ever found lurking in the deep ocean. Sometimes called a "spook fish," no doubt because of its strange appearance, the barreleye has a completely transparent head.
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.