National Geographic : 1953 Nov
+ Silver Hatchetfish Watches His World Through Astrodome Eyes Nocturnal animals such as owls and tarsiers often have abnormally large eyes, the better to catch the night's faint light. Many fish and crustaceans living near the lowest limits of the sun's penetration show the same peculiarity. One such is Argyropelecus, the tiny hatchetfish (opposite and right). His bulging eyes, set close in front of a trans parent brain case and above a cavern ous maw, hold lenses suggesting a tele scope. The eyes, like those in many other deep-sea creatures kept by the author in his seaside aquarium, became cloudy long before the animal died. Viewed from below (page 598), the slab-sided hatchetfish shows only a nar row blade studded with brilliant lights. Oddly enough the lights point down, doing little good for upward scanning eyes. Silvery pigment turns the fish's sides into a blaze of tinsel. Above: Mrs. Zahl contrasts a fully grown Argyropelecus with an enlarged drawing made for scientific illustration by Signor Filiberto Mazza of Messina's Marine Institute.