The equatorial regions may well be called the head-quarters of the lizard race, as these reptiles nowhere else appear in such a multitude of genera, species, and individuals. The stranger is struck with their numbers as soon as he sets his foot on a tropical shore, for on all sides, on the sands and in the forests, on banks and rocks, on the trees and on the ground, innumerable varieties of lizards are seen basking, rustling, crawling, climbing, or rapidly darting along. The _Geckoes_ might even claim to be ranked among the domestic animals, as they take up their abode in the dwellings of man, where they make themselves useful by the destruction of flies, spiders, and other noxious or disagreeable insects, which they almost always swallow entire, their throat being as broad as the opening of their jaws. During the day time they generally remain concealed in some dark crevice or chink, but towards evening they may be seen running along the steepest walls with marvellous rapidity, in keen pursuit of their prey, frequently standing still, nodding with their head, and uttering shrill tones, most likely by smacking their tongue against the palate. Their flattened flexible body seems to mould itself into the hollows, in which they often remain motionless for hours, and their generally dull colour harmonises so well with their resting-places, as to render them hardly distinguishable, a circumstance which answers the double purpose of masking their presence from the prey for which they lie in wait, and from the enemies that might be inclined to feast upon them. Among these, some of the smaller birds of prey--hawks and owls--are the most conspicuous, not to mention man, the arch-persecutor of almost every animal large enough to attract his notice. [Illustration: GECKO.] How comes it that these nocturnal lizards, seemingly in defiance of the laws of gravitation, are thus able to adhere to ceilings or any other overhanging surfaces? An inspection of the soles of their broad feet will soon solve the enigma, for all their toes are considerably dilated on their margins, and divided beneath into a number of transverse lamellæ, parallel to each other, and generally without any longitudinal furrow. From these a fluid exudes which serves to attach the animal to the surface. They are also generally provided with sharp and crooked claws, retractile and movable, like those of a cat, and which render them good service in climbing trees.