The Blind Octopus is different in that it has nothing BUT a blind spot!
Actually that's not quite true - they can at least see the difference between light and dark - but they certainly have some serious difficulties in the eyeball department.
For a start, they have no lens, which means they can't focus on anything. Second, they have a reduced retina, which is bad news if you want your eye to detect the shape of whatever it's pointing at.
|Image: Michael Vecchione|
And then, as if all that wasn't enough, it appears they like to go about with their transparent, elephant ear fins covering what little peeper-power they have left.
Perhaps they're protecting them from those freakishly spiky arms?