Originally created to preserve a record of scientific samples, the black and white X-rays of fish at the Smithsonian Institution have emerged as astonishing works of art in their own right. This stunning compendium of images—comparable to fine and delicate engravings—is drawn from the National Museum of Natural History, which holds the world's largest collection of ichthyological specimens. As mesmerizingly beautiful as they are amazingly detailed, these images reveal the hidden wonders of the creatures of the deep.