2. "A pelagic, or open-ocean, octopus gives off a neon glow in Hawaii. Most species of octopus have no internal skeleton, unlike other cephalopods."
3. "A photographer's strobe gives a violet sheen to this translucent juvenile roundbelly cowfish off the coast of Kona, Hawaii. Also known as the transparent boxfish, the roundbelly cowfish has two short horns in front of its eyes."
5. "Tiny marine snails known as sea butterflies take many forms, including heart-shaped, such as this species in Antarctica's Weddell Sea."
6. "A tiny jellyfish, with tentacles folded and its orange central mass visible through its transparent body, drifts in the waters of Antarctica's Weddell Sea."
7. This bizarre deep-water fish called the Barreleye (Macropinna microstoma) has a transparent head and tubular eyes. It has extremely light-sensitive eyes that can rotate within his transparent, fluid-filled shield on its head, while the fish's tubular eyes, well inside the head, are capped by bright green lenses. The eyes point upward (as shown here) when the fish is looking for food overhead. They point forward when the fish is feeding. The two spots above the fish's mouth are not eyes: those are olfactory organs called nares, which are analogous to human nostrils. (Photo by MBARI)
8. Found in Central America, from Mexico to Panama , the Glasswing Butterfly (Greta Oto) is a brush-footed butterfly where its wings are transparent. The tissue between the veins of its wings looks like glass. (Photo by Hemmy)
9. This jellyfish-like animals known as Salps feed on small plants in the water called phytoplankton (marine algae). They are transparent, barrel-shaped animals that can range from one to 10cm in length. (Photo by DM)
10. Jellyfish are free-swimming members of the phylum Cnidaria. They are found in every ocean, from the surface to the deep sea. Many jellies are so transparent that they are almost impossible to see. The one above is from the Arctapodema genus, with a size of an inch-long (2.5-centimeter-long). (Photo by Bill Curtsinger)
