National Geographic : 1968 Mar
rock hounds and mineralogists. In the dark ness it cast an invisible beam. Suddenly I saw a small moving object, then another, glowing an eerie greenish-blue. Curiously, for reasons not definitely known, sculpturatus and other scorpions fluoresce under ultraviolet light (opposite, lower).* Lorin pointed the light along the edge of a cattle feeding bin, revealing several more of the ghostly crawling creatures. He went to work with his tweezers; in half an hour we had collected more than 50. "Some nights I can catch as many as 500 this way," he said. Fortunately for us, there are scorpion col lectors other than Lorin Honetschlager. The elf owl, for example, which nests high in holes in the saguaro cactus, helps hold the desert's scorpion population in check (right). This 440 remarkable bird has learned not only how to swoop down through the darkness on the night-foraging scorpion, but also how to nip off its tail without being stung. Roadrunners, too, know how to handle scorpions; so do some snakes, and, in Africa, baboons. One-gallon Traps Aid in Desert Census Early one morning, under a sky still black and starry, I went on a hunt with another scorpion specialist, Stan Williams, a graduate student in zoology at Arizona State Univer sity. We parked our car ten miles south of Phoenix, where jagged mountains thrust up from the desert and multiarmed saguaros stand like warning semaphores. As part of his doctoral studies, Stan had embedded scores of one-gallon cans in the *See the author's "Fluorescent Gems From DavyJones's Locker," in the August, 1963, NATIONAL GEOGRAPHIC.