A Fresh Reason To Hate The Colossal Squid - Their Eyesight

"Not to be confused with the better known, but smaller Giant Squid, the Colossal Squid is the largest invertebrate known to science; it also has the largest eyes in the animal kingdom. Each one of the Colossal squid’s eyes can be up to 30 cms across, being bigger than a dinner plate and having a lense the size of an orange. These huge eyes allow the squid to see in dim light conditions, very useful for an animal that spends most of its time hunting at 2000 meters below the surface.

It must be mentioned that only sub adult colossal squid have been captured and studied thus far; full grown Colossal squid may grow up to 15 meters long. These giants would have even bigger eyes. Unlike the Giant Squid, the Colossal squid has stereoscopic vision, having a greater ability to judge distances. Even more amazing, each eye has a built-in “headlight”, an organ known as a photophore which can produce light so that whenever the Colossal squid focuses its eyes to the front, the photophores produce enough light for the squid to see its prey in the dark."

http://listverse.com/2010/12/12/10-animals-with-incredible-eyes/