The chameleon skin is entirely covered with scales of equal size which correspond to a thickening of the horny layer. The scales of the head are well differentiated and identified individually. Some become thorns, horns or ridges. The chameleon skin characteristically grows periodically throughout the life of the animal resulting in the superposition of two successive epidermic generations and the fall of one of them by moulting several times a year. Growth, and therefore moulting, slow down in older chameleons.