An illustration showing how noticeable an eye actually is, from the text The Vertebrate Eye and Its Adaptive Radiation, which looks at eyes, eyes everywhere, all kinds of eyes. The book is by Gordon L. Wells, but the illustration here comes from Hugh B. Cott, who researched protective coloration. Which of course has to do with eyes and what they see. The chapter “Possible Value of Eye Coloration” has lines like, “The difficulty of concealing the little black eyes in transparent fish larvae has been discussed previously,” and “Here, as with the eye as a whole, it is likely that the conspicuousness produced by glisten is so great that the animals have found it quite impossible to counteract the shininess by any sort of camouflage.”