Barreleyes, just a few inches long, are thought to eat small fishes and jellyfish. The green pigments in their eyes may filter out sunlight coming directly from the sea surface, helping the barreleye spot the bioluminescent glow of jellies or other animals directly overhead. When it spots prey (such as a drifting jelly), a barreleye rotates its eyes forward and swims upward, in feeding mode.
What a freak! Reminds me of a girl I used to date that had a wandering eye. My God that turned me on. When she was looking at you it was like she was looking through you. Well, with her good eye anyways, the other was always wandering over your shoulder. Damn I miss that eye.
Strange Fish Has See-Through Head [aolnews]
Thanks to Pat, who has eyes in the back of his head that he can't use because he needs a haircut.