This fish, as you can see, has an transparent head.

It's head is like a fighter- plane cockpit.

The barreleye fish shows it is highly sensitive, barrel-like eyes-topped by green, orblike lenses.

This fish was discovered alive in deep water off California's central coast by the Monterey Bay Aquarium Research Institute.

It is 6inches long and has been known since 1939 but only from mangled specimens dragged to the surface by nets.

This is the first photograph of the fish alive.