Barreleye Fish

Its so unique with the transperent head.

Deep-sea fish have adapted to their pitch-black environment in a variety of amazing ways. Several species of deep-water fishes in the family Opisthoproctidae are called "barreleyes" because their eyes are tubular in shape. Odditycentral.com stated that “The Pacific Barreleye fish gets its name from large eyes that are literally shaped like barrels, topped with beautiful green lenses. As well recognized as the Macropinna microstoma, its brain is totally lucid, filled with fluid.”

 This unique creature lives at depths of about 2000 to 2,600 feet and it is hard for us as a normal people to get a chance to see this creatures face to face. Animalspot.com - stated that the Barreleye fish were exposed by the marine biologist, Chapman in 1939. They live near the depth where sunlight from the surface fades to complete blackness. They use their ultra-sensitive tubular eyes to search for the shadowy silhouettes of prey overhead. Most of the time, the fish hangs motionless in the water with its body in a horizontal position and its eyes looking upward.

References : 

• Bebaychna, R. (n.d.). Barreleye Fish.Animal Spot. Retrieved August 18, 2014, from http://www.animalspot.net/barreleye-fish.html

• Sumitra, S. (2013, November 20). The Pacific Barreleye Fish and Its Weird See-Through Head | Oddity Central - Collecting Oddities. Oddity Central Collecting Oddities. Retrieved August 19, 2014, from http://www.odditycentral.com/pics/the-pacific-barreleye-fish-and-its-weird-see-through-head.html