GECKO, Gecko, a genus of saurian reptiles, constituting a family, geekotidce, which some recent naturalists have divided into many genera. The geckos are of small size, and generally of repulsive aspect; the colors of most of them aye dull, and the small granular scales with Which they are covered are in general mingled with tubercles. The legs are short, the gait usually slow, measured, and stealthy, although geckos can also run very nimbly when danger presses, and often disappear very suddenly when they seem almost to be struck or caught. The feet are remarkable, being adapted for adhering to smooth surfaces, so that geckos readily climb the smoothest trees or walls, or creep inverted on ceilings, or hang ou the lower side of the large leaves in which tropical vegetation abounds.. The body and tail are never crested, but are sometimes furnished with .lateral membranes, variously festooned or fringed. The lateral membrane is some times even so large as to be of use to arboreal species in enabling them to take long leaps from branch to branch Tile geckos feed chiefly on insects. They are more or
less nocturnal in their habits. They are natives of warm climates, and are very widely distributed over the world. Two species are found in the s. of Europe, both of which frequently enter houses, as do the geckos of Egypt, India, and other warm countries. The name gecko is derived from a peculiar cry often uttered by some of the species, and which in some of them resembles syllables distinctly whilst others are described as enlivening the night in tropical forests by a harsh cackle. The geckos have, in almost all parts of the,,world where they are found, a bad reputation as veno mous, and as imparting injurious qualities to food which they touch, but there is no good evidence in support of any such opinion, in. accordance with which, however, an Egyptian gecko is even known as the father of leprosy,