The tongue is the chief organ for taking the insects on which the Chameleon lives. By a curious mechanism, of which the tongue-bone is a principal agent, the Chameleon can protrude this cylindrical tongue, which has its tip covered with a glutinous secretion from the sheath at the lower part of the mouth, to the length of six inches. When the Chameleon is about to seize an insect, it rolls round its extraordinary eyeballs so as to bring them to bear on the doomed object; as soon as it arrives within the range of the tongue, that organ is projected with unerring precision, and returns into the mouth with the prey adhering to the viscous tip. The wonderful activity with which this feat is performed, forms a strong contrast to the almost ridiculously slow motions of the animal. Their operation of taking meal-worms, of which they are fond, though comparatively rapid, is not remarkable for its quickness, but done with an act of deliberation, and so that the projection and retraction of the tongue can be very distinctly followed with the eye. The eyes of the Chameleon are remarkable objects; large, projecting, and almost entirely covered with the shagreen-like skin, with the exception of a small aperture opposite the pupil; their motions are completely independent of each other. It adds to the strange and grotesque appearance of this creature to see it roll one of its eye-globes backwards, while the other is directed forwards, as if making two distinct surveys at one time. Its sight must be acute, from the unerring certainty with which it marks and strikes its prey. The Chameleons spend their lives in trees, for clinging to the branches of which their organization is admirably adapted. There they lie in wait for the insects which may come within their reach; and it has been thought that, in such situations, their faculty of changing colour becomes highly important in aiding them to conceal themselves. The powers of abstinence possessed by this singular race are very great; and hence, most probably, arose the old fable of their _living on air_, which was for a long time considered to be "the Chameleon's dish." One has been known to fast upwards of six weeks without taking any sustenance, though meat-food and insects were procured for it. Notwithstanding this fast, it did not appear to fall away much. It would fix itself by the feet and tail to the bars of the fender, and there remain motionless, enjoying the warmth of the fire for hours together. Hasselquist describes one, that he kept for nearly a month, as climbing up and down the bars of its cage in a very lively manner.